Maximum greenhouse gases are released by

Match the following and choose the correct combination from the options given:
Column $I$ | Column $II$
$(1)$ $DDT$ | $(p)$ $CO, CO_2$
$(2)$ $PAN$ | $(q)$ Smog
$(3)$ Acid rain | $(r)$ Biological magnification
$(4)$ Global warming | $(s)$ $SO_2$

If an agricultural field is liberally irrigated for a prolonged period of time,it is likely to face the problem of:

Match the following important dates/events related to environmental legislation in India:
$(i)$ Air (Prevention and Control of Pollution) Act
$(ii)$ Environment (Protection) Act
$(iii)$ Water (Prevention and Control of Pollution) Act $(1974)$

The most common pesticide used in India is

Burning of fossil fuels affects which of the following cycles?