Which of the following radiatively active gases contributes the least to global warming?

1. CO₂

2. CFC

3. N₂O

4. CH₄

Which of the following commits industrialized nations to reduce greenhouse gas emissions ?
1. Montreal protocol
2. Kyoto protocal 
3. UNECD earth summit
4. Alma Atta conference 

To safeguard our water resources, the Water (Prevention and Control of Pollution) Act, was passed in:

1. 1951
2. 1974
3. 1985
4. 1987

Eventually, the only solution for the treatment of e-wastes, provided it is carried out in an environment friendly manner, is:
1. Incineration
2. Burying in landfill sites
3. Dumping in developing countries
4. Recycling

Match each item in Column I with one item in Column II and choose the correct answer from the code given below:

Codes:
             A.            B.                   C.              D.
1.          a              b                    c               d

2.          b              a                    d               c

3.          d              c                    b               a

4.          c              d                    a               b

What is eutrophication?

1. The nutrient enrichment of lakes and ponds
2. The decrease in the pH of a lake or pond
3. The increase of water temperature of a lake or pond
4. The depletion of nutrients inlakes and ponds

In what way does thermal pollution affect organisms?
1. Lowers the pH of water
2. Interrupts normal physiological pathways
3. Decreases oxygen supply in water
4. Increases oxygen supply in water

Which of the following is not likely to happen as a result of the rising levels of ${\mathrm{CO}}_2$ in our atmosphere?

1. Increased incidents of skin cancer

2. Rise in sea levels

3. Change in climatic patterns

4. Shifts in locations of deserts and fertile regions

The UN Conference of Parties on climate change in the year 2011 was held in 

(1) Poland

(2) South Africa

(3) Peru

(4) Qatar

Which one of the following statements is not valid for aerosols ?

1. They are harmful to human health
2. They alter rainfall and monsoon patterns
3. They cause increased agricultural productivity
4. They have negative impact on agricultural land