In an ecological crisis,whose interference plays an important role?

Petroleum is a ......... source.

At the beginning of the $20^{th}$ century,forests covered about $.....P.....$ of the land in India. By the end of the century,this had shrunk to $.....Q.....$.

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 | $(s)$ $SO_2$

World Environment Day is celebrated on

Which of the following options correctly represents the full name and its abbreviation?