16. Assertion (A) : After carbon, nitrogen is the most abundant element in the biosphere.
    Reason (R) : Nitrogen is essential for synthesizing the living matter in nature.
    Code

1. 1. Both (A) and (R) are individually true and (R) is the correct explanation of (A)
      

   
   
   

   2. Both (A) and (R) are individually true but (R) is not the correct explanation of (A)
      

   
   
   

   3. (A) is true but (R) is false
      

   
   
   

   4. (A) is false but (R) is true
      

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: B

   NA

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17. Assertion (A) : The habitat of Date Palms is warm deserts with little of no rainfall.
    Reason (R) : Date Palm is a tree of waterless desert.
    Code

1. 1. Both (A) and (R) are true and (R) is the correct explanation of (A)
      

   
   
   

   2. Both (A) and (R) are true but (R) is not the correct explanation of (A)
      

   
   
   

   3. (A) is true but (R) is false
      

   
   
   

   4. (A) is false but (R) is true
      

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: C

   NA

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18. Consider the following statements
    1. Biodiversity hotspots are located only in tropical regions.
    2. India has four bio-diversity hotspot i.e., Eastern Himalayas, Western Himalayas, Western Ghats and Andaman and Nicobar Islands.
    Which of the statements given above is / are correct ?

1. 1. 1 only

   
   
   

   2. 2 only

   
   
   

   3. Both 1 and 2

   
   
   

   4. Neither 1 nor 2

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   NA

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19. The flow of energy

1. 1. Decrease with each successive tropic level

   
   
   

   2. Increase with each successive tropic level

   
   
   

   3. Remains constant with each successive tropic level.
      

   
   
   

   4. First increase and then decrease with each successive tropic level

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: A

   NA

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20. Consider the following pairs of projects and related environmental problems
    1. River Valley project : Water body induced
    2. Mining project : Ground water and surface water pollution
    3. thermal power project : Degradation of land
    Which of the above pair (s) is / are correctly matched ?

1. 1. 1, 2 and 3

   
   
   

   2. 2 and 3

   
   
   

   3. 1 and 2

   
   
   

   4. 1 alone

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: A

   NA

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