The correct answer is option B. According to the scientific classification made by the United States Department of Agriculture (USDA - 1982), 'Eridisols' (sandy soil zone) are mainly found in the arid and semi-arid climatic conditions of Rajasthan. This soil is found in wide areas of Churu, Sikar, Jhunjhunu, Nagaur, Didwana-Kuchaman, Jodhpur, Phalodi, Pali and Jalore districts of the state. Its main sub-soil is 'Orthids', under which Camboorthids, Calciorthids and Paleorthids are present in Rajasthan. The area described in option A is of Vertisols (black soil), option C is of Alfisols (alluvial soil) and option D is related to Inceptisols and red-loamy soil.

The correct answer is option B (Statements A, B and D are true, while statement C is false). Alfisols soils develop in sub-humid and humid climate regions and represent alluvial/alluvial soils formed by old and new rivers. Alfisols soil is found in the eastern and south-eastern districts of the state like Jaipur, Alwar, Dausa, Bharatpur, Deeg, Tonk, Sawai Madhopur, Bhilwara, Chittorgarh, Kota, Baran, Jhalawar etc. Statement C is false because Aridisols and Entisols soils are found in the Thar Desert, not Alfisols. Alfisols are very rich in terms of fertility and agricultural production is excellent in it.

The correct answer is option A (A-2, B-1, C-4, D-3). Entisols are soils found in the desert dry region of entire western Rajasthan which can be found in different climatic conditions (A-2). Vertisols are black soils rich in clay which are widespread in the south-eastern Hadoti region, Jhalawar, Kota, Bundi and Baran (B-1). Inceptisols are an area of ​​rocky soil which is never found in dry climate, it is found in the Aravali slopes of Sirohi, Pali, Rajsamand, Udaipur and Bhilwara (C-4). Aridisols are found in semi-arid climate like Churu, Sikar, Jhunjhunu, Nagaur etc. (D-3).

The correct answer is option C. Under scientific classification, Vertisols soil contains excessive amount of clay, due to which it has high water holding capacity. This soil is found in humid and ultra-humid climatic zones and is widespread in most parts of Jhalawar, Kota, Bundi and Baran districts of south-eastern Hadoti plateau of Rajasthan. Aridisols are found in dry western Rajasthan, Alfisols in the eastern plains and Inceptisols in the Aravalli mountain slopes (Sirohi, Pali, Udaipur).

The correct answer is option B (Statements A, C and D are true, Statement B is false). Statement B is false because Inceptisols (stony soils) are never found in dry climates; It is found in the Aravalli region with sub-humid climate in Sirohi, Pali, Rajsamand, Udaipur and Bhilwara districts. Entisols and Aridisols predominate in Jaisalmer and Barmer. Sandy soils i.e. Aridisols and Entisols are widespread in about 60-65% (two-thirds) of Rajasthan. The major components of Entisol class are Samants and Fluvents, which are found in almost all the districts of Western Rajasthan.

The correct answer is option A (A-3, B-2, C-1, D-4). According to the 14-level soil classification of Rajasthan Agriculture Department: Sie Rozems and Reverita soils are mainly found in Sriganganagar district (A-3). Gypsiferous soil is found only in Bikaner district where there are abundant reserves of gypsum (B-2). Red Loam soil is widespread in Dungarpur and Banswara districts of southern Rajasthan (C-1). New alluvial soil is the fertile soil brought by rivers which is found in Jaipur, Alwar, Bharatpur, Deeg and Sawai Madhopur (D-4).

The correct answer is option B. According to the soil classification table presented by the Rajasthan Agriculture Department, both 'Sai Rosems' and 'Reverita' types of soils are found in Sriganganagar district of north-western Rajasthan. Riverita soil is formed from the alluvial deposits of the Ghaggar River. Gypsiferous soil is mainly found in Bikaner, mountainous and red-loamy soil is found in Udaipur and gray brown alluvial and saline soil is found in Jalore.

The correct answer is option A (Statements A, B and D are true, while statement C is false). Statement C is false because 'non-calcite brown' soil is found in Jaipur, Sikar, Jhunjhunu, Nagaur, Ajmer and Alwar districts and not in Jalore and Balotra. Calcareous brown soil is widespread in Jaisalmer and Bikaner. According to the Agriculture Department, the extension of deep medium black soil has been considered in Kota, Bundi, Bhilwara, Chittorgarh, Bharatpur, Deeg and Jhalawar. New brown soil is found in the middle districts of Aravalli, Bhilwara, Beawar and Ajmer.

The correct answer is option A. In the desert/sandy soil region of western Rajasthan, due to lack of rainfall and high evaporation, a layer of alkaline salts like sodium and calcium carbonate accumulates in the soil. Its pH value is high (above 8). There is severe deficiency of organic matter (humus), nitrogen and organic salts in this soil. Due to it being porous, it gets easily transferred by air. Option B is characteristic of acidic soil and option C is characteristic of red soil.

The correct answer is option B (Statements A, B and C are true, Statement D is false). Statement D is false because the particles of sandy sand soil are coarse, due to which it has very low water storage/holding capacity and water seeps down quickly; That is why it is generally less fertile for agriculture. Due to presence of mixed layer in yellow-brown sandy soil, it is called steppe soil which is widespread in Nagaur, Pali and Didwana-Kuchaman. Saline soil develops in low drainage and saline areas.

The correct answer is option B. The color of Sirozem soil is yellow-brown or grey-painted. It is found in the areas with small sand dunes to the west of Aravali like Pali, Beawar, Ajmer, Nagaur, Didwana-Kuchaman and Jaipur. There is severe lack of nitrogen and organic matter (humus) in this soil, due to which its natural fertility is relatively low. In this context, statement (A) low fertility and reason (R) lack of nitrogen and organic matter, both are mutually true.

The correct answer is option A (A-2, B-1, C-3, D-4). Alluvial soil is a fine grained soil formed by rivers which is rich in potash and is the most fertile (A-2). Medium black soil is predominantly clay/loamy, which swells when wet and cracks when dry (self-cultivating soil) (B-1). Red-loamy soil has red color due to fine particles of iron oxide (C-3). Due to alkaline salts in saline soil, it is called Usar, Kallar or Reh (D-4).

The correct answer is option B. Brown soil is mainly found in the eastern part of the Aravali mountain range in the water catchment area of ​​Banas river and its tributaries (Berach, Kothari, Khari etc.). Its main expansion is in Tonk, Ajmer, Sawai Madhopur, Bhilwara, Beawar and Udaipur districts. This soil is deficient in nitrogen and phosphorus salts, but with proper water management it remains suitable for agriculture. Red-loamy soil is widespread in southern Rajasthan and black soil is widespread in Hadoti.

The correct answer is option B (Statements A, B and C are true, while statement D is false). Statement D is false because 'Regur soil' is the name of black soil and not of alluvial soil. Alluvial (alluvial/loamy) soil is found in the river plains in the northern and eastern parts of the state. It contains adequate amount of potash but lacks lime, phosphorus, humus and nitrogen. This is a very suitable and fertile soil for wheat, cotton, mustard and tobacco crops.

The correct answer is option B. Red loam soil is formed by the erosion of ancient crystalline and metamorphic rocks. Iron oxide compounds are present in abundance in this fine grained soil, due to which its color appears red. This soil is deficient in phosphorus, nitrogen, calcium and humus. It is found in some parts of Dungarpur, Banswara, Udaipur, Salumber and Chittorgarh of southern Rajasthan and is famous for the cultivation of maize and cotton.

The correct answer is option A (A-2, B-3, C-4, D-1). Red and yellow soil is found in Sawai Madhopur, Ajmer, Bhilwara, Sirohi and Rajsamand (A-2). Mixed red and black soil is found in Dungarpur, Banswara, Bhilwara and Chittorgarh as an extension of the Malwa plateau (B-3). Mountain soil is found in the hill slopes of Aravali in Udaipur, Sirohi, Ajmer and Kota (C-4). Gypsiferous soil is found only in Bikaner district (D-1).

The correct answer is option B (Statement A, B and D are true, Statement C is false). Statement C is false because laterite soil is the result of intense leaching, due to which nutrients from its upper levels dissolve and run down; Therefore, there is severe deficiency of nitrogen, phosphorus, calcium and humus in it. It contains only iron oxide and some potash. Due to excessive leaching this land is very less fertile for agriculture. It is found in the hilly parts of Dungarpur, Udaipur and Rajsamand.

The correct answer is option B. Medium black soil (Regur / Kapasi Soil) is formed by erosion of basalt lava in Hadoti region (Kota, Bundi, Baran, Jhalawar). Its particles are dense and fine (Chica dominant), due to which it has the ability to retain moisture/water for a long time. When it gets wet, it swells and when it shrinks when it dries, deep cracks appear in it, which is also called 'self-cultivating soil'. It is considered highly fertile and best for the cultivation of cotton, soybean and paddy.

The correct answer is option A (Statements A, B and C are true, while statement D is false). Statement D is false because most of the red, yellow and mixed red-black soils of Rajasthan are generally deficient in phosphorus, nitrogen, calcium and organic matter (humus). Red-yellow soil formed by the disintegration of granite, schist and gneiss rocks is found in Sawai Madhopur, Bhilwara, Ajmer and Sirohi and appears yellow due to hydration. Mixed red-black soil is famous for maize and cotton in Bhilwara, Chittorgarh, Banswara and Udaipur.

The correct answer is option B. In alkaline soil, alkaline salts like sodium carbonate, sodium chloride etc. are found in excessive amounts, due to which a white crust forms on the upper surface of the soil. This infertile soil is called Usar, Kallar, Reh, Alkaline or salty soil in the local language. This soil is found in highly irrigated or low drainage areas of Barmer, Balotra, Jalore, Sriganganagar, Deeg and Bharatpur districts.

The correct answer is option C. In Rajasthan, the highest percentage of waste land in terms of area is found in Jaisalmer district (68.34%). After this, Rajsamand (48.91%), Bikaner (39.15%) and Udaipur (36.31%) districts come respectively. Jaisalmer has the highest proportion of waste land due to extreme dryness, expanse of sand dunes and rocky desert (Hamada).

The correct answer is option D (All statements A, B, C and D are true). The pH value of normal balanced soil is 6.5 to 7.5. When pH is more than 7, the soil is called alkaline or saline and when it is less than 6.5, it is called acidic (deficiency of lime). The primary/main nutrients of soil are nitrogen, phosphorus, potash and organic sulphur. Whereas boron, manganese, zinc, copper and iron come in the category of micro/secondary nutrients. Potash has been considered the main element in the test.

The correct answer is option B. In the western part of Rajasthan, due to low rainfall and high evaporation, the salt below rises up through the cells and gets deposited (capillary action). Gypsum is used for long-term treatment of the problem of salinity and alkalinity in soil. Gypsum improves soil structure by displacing sodium. Huge reserves of gypsum are found in Nagaur, Bikaner and Barmer. Lime or rock phosphate is used to treat acidic soil.

The correct answer is option D (All statements A, B, C and D are true). 'Sem' (Sem) is a marshy and saline ecological problem caused by water leakage and excessive irrigation in Indira Gandhi Canal and Chambal irrigated areas. Due to the hard gypsum/rock layer at the bottom of the canal, water spreads around instead of going down, causing underground salts to accumulate on the surface by capillary attraction. 'Badopal' village of Hanumangarh is most affected by this. 'Rajad Project' was run with the cooperation of Canada in 1992-93 to remove beans in Chambal irrigated area.

The correct answer is option B. There is a underground water belt spread between Nagaur, Didwana-Kuchaman and Ajmer districts, which is called 'Banka Patti' or 'Kubadpatti'. The amount of fluoride in the water here is found to be excessive (many times more than the safe limit). Continuous drinking of fluoridated water causes 'fluorosis' disease in the residents, due to which the bones become crooked and the waist gets bent (hunchback). Jayal area of ​​Nagaur is especially famous for fluoride rich water.

The correct answer is option A (A-3, B-1, C-2, D-4). Gully erosion is highest in the Chambal river region (Kota, Karauli, Dholpur, Sawai Madhopur) due to which ravines and ravines are formed (A-3). Wind erosion occurs in most parts of Rajasthan (western desert districts Jaisalmer, Barmer, Bikaner) due to winds (B-1). Sheet erosion is the washing away of the upper layer of soil by rain water which occurs on the mountain slopes of Sirohi and Rajsamand (C-2). Waterlogging occurs in Hanumangarh and Sriganganagar (D-4).

The correct answer is option B (Statements A, C and D are true, while statement B is false). Statement B is false because excessive use of chemical fertilizers harms the health of the soil and increases erosion and chemical toxicity by destroying its biological structure, rather than preventing it. Soil erosion destroys the fertile layer, hence it is called 'creeping death'. Tree plantation, controlled animal grazing, crop rotation and contour plowing are the main means of soil conservation.

The correct answer is option B. The rapid water flow of Chambal river and its tributaries causes deep soil erosion, due to which thin drains turn into deep gullies. The rough topography with 5 to 30 meter deep ravines and uneven valleys created by this process is called 'Badland Topography' or 'Ravine Lands'. In the local language these ravines are also called 'Khadar'. The largest expanse of rugged land is in Sawai Madhopur, Karauli, Dholpur and Kota districts.

The correct answer is option A (A-2, B-1, C-4, D-3). On the basis of nature and direction, the drainage system of Rajasthan is divided into three parts: Internal flow system is the largest drainage system of the state which is spread over about 60% of the area (A-2). The rivers carrying water to the Bay of Bengal (Chambal, Banas etc.) occupy about 24% area (B-1). The rivers falling into the Arabian Sea (Luni, Mahi, Som, Jakham) occupy about 16% of the area (C-4). The Ghaggar river basin is mainly spread in Hanumangarh and Sriganganagar districts (D-3).

The correct answer is option C. The Jakham River is not a river of the internal drainage system; It is a tributary of the Mahi River which ultimately discharges its waters into the Arabian Sea through the Som-Mahi Sangam (Veneshwar). Internal drainage rivers of Rajasthan are those rivers which do not reach any sea and become extinct in their flow area, like Ghagghar, Kantli, Kakani (Kankani/Masurdi), Sabi, Ruparel, Mantha, Rupangarh, Lik, Khandel etc.

The correct answer is option D (All statements A, B, C and D are true). Ghaggar River is considered to be the remnant of the ancient Vedic Saraswati/Dvaishwati River. It originates from Shivalik hills and enters Tibbi tehsil of Hanumangarh via Haryana. In Rajasthan, its flow area is called 'Nali' or 'Paat' and generally it disappears near Bhatner. In case of extreme floods, its water reaches 'Fort Abbas' located in Bahawalpur, Pakistan, where its flow area is called 'Hakra'. Talwara Lake of Hanumangarh is situated on this river.

The correct answer is option A. The flow area of ​​Ghaggar River located in Rajasthan (Hanumangarh and Sriganganagar) is called 'Naali' or 'Paat' in the local language. When the river swells, its water enters Pakistan, where its flow area is called 'Hakra' and its end point is 'Fort Abbas' (Bahawalpur, Pakistan). Khadar is called the ravines of Chambal and Kubadpatti is called the fluoride affected area.

The correct answer is option A (A-3, B-1, C-2, D-4). Kantli river originates from Khandela hills of Sikar, cutting Jhunjhunu into two parts and ends at the border of Churu (A-3). Kakani (Kankani/Masoordi) river originates from Kotri village in Jaisalmer and forms Bujh Lake (B-1). The Sabi River originates in the Sewar hills of Jaipur and disappears in the Pataudi tehsil of Gurgaon (Gurugram) in Haryana (C-2). Mantha River originates from Manoharpur (Jaipur) and falls into Sambhar Lake from the north (D-4).

The correct answer is option D (All statements A, B, C and D are true). Ghaggar river is called Dead River, Nat, Sotar and ancient Dvaishwati/Saraswati. The small Kakani river of Jaisalmer is called 'Masoordi'. The Kantli River (100 km) is the longest internal drainage river flowing entirely within the state of Rajasthan (whereas the Ghaggar is the longest internal drainage river in terms of total length). Ghaggar River is the only river that originates from the Shivalik ranges of the Himalayas and comes to Rajasthan.

The correct answer is option C. Ghaggar River is the only river in Rajasthan that enters the state (Hanumangarh district) from the north. It has been given the likeness of 'Dead River' because its flow often remains dry except during the rainy season and it ends in the plains of Rajasthan. Chambal and Mahi rivers enter Rajasthan from the south, while Kantli river originates from Sikar (Aravalli). The famous Kalibanga and Pilibanga civilizations developed at the mouth of the Ghaggar river.