Statements A, B and D are completely true, while statement C is false. According to the rules of physical geography, the temperature decreases by 1^{\circ}C$ for every 165 meters of height, and not increases. Rajasthan falls in the subtropical zone between $23^{\circ}03^{\prime}$ to $30^{\circ}12^{\prime}$ northern latitude and due to its extreme distance from the sea, the temperature difference is high here and continental climate is found. Mount Abu is the coldest place in the state due to its location at a high altitude. Option A is the correct answer because statement C being wrong automatically eliminates the remaining options B, C and D.

Statements A, C and D are true, but statement B is false. The monsoon branch of the Arabian Sea passes parallel to the direction of the Aravalli mountain range (from south-west to north-east), and not perpendicularly. Due to flowing parallel to it, the winds are not able to rise above the Aravalli and move towards the north without causing rain. On the contrary, the Bay of Bengal branch hits Aravali at right angles/perpendicularly and due to condensation gives good rainfall in Hadoti and eastern plains. Hence option A is the correct answer.

Option D is a false/mismatched pair. In general climate classification, Rajasthan is divided into 5 parts on the basis of rainfall. In this very humid zone, the average annual rainfall ranges from 80 to 120 cm (not 60-80 cm). The area with 60 to 80 cm rainfall is called Humid Zone, which includes the eastern plains. Rainfall is 0-20 cm in the dry region, 20-40 cm in the semi-arid region and 40-60 cm in the sub-humid Aravalli region. Hence option D is the correct answer.

The correct matching is A-4, B-3, C-1, D-2. Dry tropical climate is found in the western Thar Desert (0-20 cm rainfall). Sub-humid climate is found in the Aravali mountain region (40-60 cm rainfall). Humid climate is found in the eastern plains (60–80 cm rainfall), while extremely humid climate is prevalent in the Hadoti plateau and southern Vagad region/Mahi basin (80–120 cm rainfall). All other options represent incorrect matches, hence option A is the correct answer.

Statements A, B and D are true, while statement C is completely false. In the Köppen classification, the 'E' symbol indicates tundra/snowy climate, which occurs in areas with extreme cold and snow. There is no such extreme cold or snowfall in Rajasthan, hence E type climate is absent in Rajasthan. BWhw refers to dry hot desert where zerophyte thorny vegetation is found due to lack of water. Hence only option A is the correct answer.

According to Köppen, the largest climatic region of Rajasthan in terms of area is BShw (semi-arid or steppe-like climate). This region includes Luni Basin (Jodhpur, Pali, Barmer, Balotra, Jalore), Nagaur, Didwana-Kuchaman, and Shekhawati region (Sikar, Jhunjhunu and parts of Churu). Steppe type short grass is found here, due to which animal husbandry has developed. BWhw is the far western dry part, Cwg is the eastern and central part and Aw is the smallest southern part. Hence option B is the correct answer.

The correct combination is A-4, B-3, C-2, D-1. Due to extreme dryness in BWhw region, xerophyte thorny vegetation is found (Jaisalmer, Bikaner, Sriganganagar). Steppe grass (Luni Basin, Nagaur, Shekhawati) is found in BShw region. Monsoon deciduous trees are found in the Cwg sub-humid region (eastern plains - Alwar, Bharatpur, Jaipur, Ajmer), while dense savanna vegetation is found in the Aw super humid region (Wagad region - Banswara, Dungarpur, Pratapgarh). Hence option A is the correct answer.

Statements A, B and D are true, while statement C is false. In the classification of Trivartha, the average rainfall of Aw (very humid/savanna) region is 100 cm, whereas the average rainfall of BWh (dry desert) region is only 10 cm. In statement C the data have been reversed. Trivartha considered rainfall and hot summer as the main basis and named Köppen's Cwg as Caw in which 70 cm average rainfall is considered. Hence option A is the correct answer.

The classification of Charles Warren Thornthwaite (C.W. Thornthwaite) is considered to be the most accepted and scientific among the individual classifications because it prominently includes not only rainfall and temperature but also evaporation (the rate at which water evaporates). In arid and semi-arid areas, the rate of evaporation is more than the water yield, hence Thornthwaite's model fits well for a climate like Rajasthan. Hence option B is the correct answer.

Statements A, B and C are true, while statement D is false. EA'd (dry desert equivalent) in Thornthwaite's classification is located in far western Rajasthan (Jaisalmer, Barmer, West Jodhpur, Bikaner). Northern Rajasthan (Sriganganagar, Hanumangarh) has a DB'w (arid-semi-arid) climate, not EA'd. Rajasthan being an overall dry state, A and B categories are not found here and DA'w is the largest state. Hence option A is the correct answer.

The correct combination is A-3, B-4, C-1, D-2. The CA'w sub-humid region covers the Vagad (Banswara, Dungarpur) and Hadoti regions of southern Rajasthan. DA'w semi-arid region is spread in central and eastern Rajasthan (Ajmer, Jaipur, Bhilwara etc.). DB'w is spread in dry-semi-arid northern Rajasthan (Sriganganagar, Hanumangarh) and EA'd dry desert region is located in western Jaisalmer-Barmer. Hence option A is the correct answer.

Statements A, B and D are true, while statement C is false. In Rajasthan, maximum number of storms occur in Sriganganagar district (about 27 days in a year), while minimum number of storms occurs in Jhalawar district (only 2 days). In statement C the names of the districts have been interchanged. Heat wave increases the temperature through horizontal advection, while typhoon decreases the temperature through convection process. Bhabhulya is a circular tornado generated due to central low pressure. Hence only option A is the correct answer.

Option D is a false statement. The hottest month in Rajasthan is June (when the temperature reaches its highest level) and the coldest month is January. In option D both the months have been interchanged. The daily temperature difference (difference between day and night temperatures) is highest in Jaisalmer due to the desert sandy soil, while the annual temperature difference (difference between summer and winter temperatures) is highest in Churu. Sirohi/Mount Abu remains the coldest due to its altitude. Hence option D is the correct answer.

Statements A, B and C are true, while statement D is false. Monsoon reaches the whole of India by 15 July (not 15 August). The most unique feature of monsoon in Rajasthan is its shortest duration – it arrives late (2 June) and retreats early (30 September). The first arrival in Rajasthan is from Banswara-Dungarpur (Wagad). Hence option A is the correct answer.

The correct combination is A-2, B-4, C-1, D-3. Due to flowing parallel to the Aravali, the Arabian Sea branch passes without colliding and receives less rainfall. The branch of the Bay of Bengal hitting the Aravalli perpendicularly gives maximum rainfall in Rajasthan. Monsoon winds coming from the Bay of Bengal are called 'Purvai' in the local language. Vajra storm refers to rain accompanied by lightning and strong winds in the south-eastern districts. Hence option A is the correct answer.

Option D is the incorrect statement. In Jaisalmer and Bikaner, rainfall is only around 10 to 20 cm, where the iso-rain line of 10 cm is found. Rainfall of 100 cm or more is possible only in Mount Abu or the extremely humid Hadoti/Jhalawar region. The 25 cm line divides the desert, the 40 cm line forms the eastern boundary of the desert and the 50 cm line acts as a watershed along the Aravali. Hence option D is the correct answer.

Statements A, C and D are true, but statement B is false. According to the rules of climate science, there is an inverse relationship between the amount of rainfall and uncertainty/variability. Where rainfall is high (e.g. Jhalawar/Mount Abu), the uncertainty of monsoon is less. Where rainfall is low (e.g. Jaisalmer/Barmer), uncertainty is extremely high. Hence option A is the correct answer.

Autumn (October-November) is the transition period of retreating monsoon. At this time, the moisture in the atmosphere starts decreasing and the sky becomes clear, due to which the sunlight becomes stronger. Immediately after the rainy season, there is soil moisture left in the ground, which evaporates due to intense sunlight and creates humid and sticky heat in the air. This situation is called 'Karthik heat' or 'October heat'. Hence option B is the correct answer.

Statements A, B and D are true, while statement C is false. Mavath (winter rains) proves to be a boon for Rabi crops (mainly wheat, gram, mustard) and not for Kharif crops. Rabi crops are sown in winter and due to the water of Mawath, they yield very good grains, that is why they are called 'Golden Drops'. Western disturbances reach India along with the jet stream. Hence only option A is the correct answer.

The correct combination is A-3, B-1, C-4, D-2. The hot dry wind of summer is called 'Loo'. A small circular rotating dust cyclone is called 'Bhabhulya'. During winter, the extremely cold wind coming from the north-east direction is called 'cold wave' and the rain that occurs before the arrival of monsoon is called 'Dongra' in the local language. Hence option A is the correct answer.

Option D is a false pair. The driest and least rainfall district of Rajasthan is Jaisalmer (not Churu). Churu district is famous for its highest summer temperature and highest annual temperature variation, but the driest district is Jaisalmer where the annual rainfall is only 10-15 cm. Mount Abu is called 'Shimla of Rajasthan' due to extreme humidity and coolness and Jhalawar/Mount Abu is called 'Cherrapunji of Rajasthan' due to maximum rainfall. Hence option D is the correct answer.

Statements A, B and C are true, but statement D is false. Winds always flow from high pressure to low pressure, and not from low to high. During summer, the Thar Desert becomes extremely hot and becomes a center of low air pressure, due to which monsoon winds are drawn from the high air pressure of the Indian Ocean. During winter the land cools down and becomes a high pressure area. Hence option A is the correct answer.

The famous 'Chhappaniya famine' occurred in 1899-1900 AD. At that time, Vikram Samvat 1956 was going on according to the Indian calendar. In the folk dialect, it was called 'Chhappaniya Akal' after the last two digits '56' of Samvat 1956. This was the most devastating famine in the history of Rajasthan in which there was a severe crisis of food, water and fodder. Hence option B is the correct answer.

All statements A, B, C and D are completely true. As per the latest update, monsoon 2025 was the second wettest year in the history of Rajasthan (715.9 mm), which was 64% above normal. The record of 1917 (844.2 mm) is in first place. On 23 August 2025, Nainwan (Bundi) received 502 mm rainfall in 24 hours, an unprecedented single-day extreme event. Hence option D is the correct answer.

All the above statements are true. In the heat wave of 2026, Phalodi touched a record temperature of $51^{\circ}C$, while Churu recorded $50.5^{\circ}C$, the highest in India in the last 8 years. These new data confirm the fact of traditional geography of Rajasthan that Phalodi is the hottest place in the state and Churu is the hottest district. Hence option D is the correct answer.

All statements A, B, C and D are true. According to the research of Max Planck Institute, there has been a change in the rainfall pattern of Rajasthan after 1950. Now the amount of rainfall in western Rajasthan is increasing by 20-35%, due to which greenery is increasing in the Thar Desert and the rate of desertification is decreasing. However, uncontrolled exploitation has also led to new environmental concerns such as decline in groundwater levels and increase in night minimum temperatures. Hence option D is the correct answer.

The correct combination is A-3, B-4, C-1, D-2. On June 21, the Sun shines directly on the Tropic of Cancer, causing the longest day and shortest night in Rajasthan. Rajasthan has the shortest day and longest night when the Sun shines directly on the Tropic of Capricorn on 22 December. Monsoon reaches Kerala in India on 1st June and 30th September is considered to be the date of official withdrawal of monsoon from Rajasthan. Hence option A is the correct answer.

The Tropic of Cancer (23\frac{1}{2}^{\circ}$ north latitude) touches the border of Dungarpur district in the far southern part of Rajasthan and passes through the middle of Banswara district (Kushalgarh). This is the reason that Banswara is a district with direct rays of the sun and most part of Rajasthan falls in the subtropical zone from latitudinal point of view. Hence option A is the correct answer.

All statements A, B, C and D are true. The 10 cm line passes through Jaisalmer-Phalodi-Bikaner in the far west. The 50 cm line forms a watershed parallel to the Aravalli. 80-90 cm rainfall line is found in very humid Hadoti and Vagad areas (Jhalawar, Kota, Baran, Pratapgarh, Banswara). Highest rainfall occurs in Jhalawar (about 100 cm) and second highest rainfall occurs in Banswara. Hence option D is the correct answer.

The correct combination is A-2, B-4, C-1, D-3. According to Köppen, the largest climatic region of Rajasthan is BShw (semi-arid/steppe). According to Thornthwaite, the largest climatic region is DA'w (semi-arid). In the general classification, semi-arid region (20-40 cm) is the widest desert transition zone and in Trivartha, BShw (30 cm rainfall) is the largest region. Hence option A is the correct answer.

Statements A, B and C are true, but statement D is false. As altitude increases, the air becomes less dense and the temperature decreases by $1^{\circ}C$ for every 165 meters, rather than increasing. For this reason, mountainous areas (like Mount Abu) remain much cooler than the plains. Due to distance from the sea, the temperature difference between day and night and summer and winter is very high. Hence option A is the correct answer.

Light showers/rainfalls that occur in late summer (May-June) before the formal arrival of monsoon in Rajasthan are called 'Dongda' in the local language. 'Mawath' refers to winter rains, 'Purvai' refers to the monsoon wind coming from the Bay of Bengal and 'Bhabhulya' refers to cyclonic dust storms. Hence option B is the correct answer.

All statements A, B, C and D are completely true. Phalodi is the hottest place with the highest temperature ($51^{\circ}C$). Churu is the district with the highest annual temperature variation and summer. Sam (Jaisalmer) has a vegetationless area with zero rainfall and Jhalawar is called Cherrapunji of Rajasthan due to the highest rainfall (more than 40 days of rainfall). Hence option D is the correct answer.

The correct combination is A-4, B-3, C-2, D-1. Xerophyte thorny vegetation is found in the extremely dry BWhw region. Steppe grass is found in the semi-arid BShw region. Dry monsoon deciduous trees Cwg are found in the sub-humid eastern plains and dense vegetation of the Savanna type is found in the very humid regions of Vagad and Hadoti Aw. Hence option A is the correct answer.

Statements A, B and C are true, but statement D is false. According to recent research and studies, due to increase in the amount of rainfall and spread of greenery in the Thar Desert, there are indications of a decrease in the rate of desertification, and not a continuous increase. The 1917 monsoon record was 844.2 mm, the 2025 monsoon was the second highest at 715.9 mm and the historical average is 57.5 cm. Hence option A is the correct answer.