The statements that are $TRUE$:
$A$. Methane leads to both global warming and photochemical smog.
$B$. Methane is generated from paddy fields.
$C$. Methane is a stronger global warming gas than $CO_2$.
$D$. Methane is a part of reducing smog.
Choose the most appropriate answer from the options given below:

Consider the following reactions involving some atmospheric pollutants:
$NO + O_3 \rightarrow NO_2 + O_2$
$NO_2 \xrightarrow{h \nu} NO + O$
$O + O_2 \rightarrow O_3$
$4 NO_2 + O_2 + 2 H_2 O \longrightarrow 4 HNO_3$
$3 CH_4 + 2 O_3 \longrightarrow 3 H_2 C = O + 3 H_2 O$
Based on the above,the formation of formaldehyde from methane in the atmosphere will be controlled by:

An increase in the concentration of $CO_2$ in the atmosphere will result in ........

What are the major pollutants in large cities?

Match the activities given in List-$I$ with the pollution produced in List-$II$.

List-$I$	List-$II$
$(A)$ Burning sulfur-containing waste releases gases into the atmosphere.	$(1)$ Water pollution
$(B)$ Use of carbonates as pesticides	$(2)$ Photochemical smog,damage to plant life,corrosion of buildings,respiratory problems,water pollution.
$(C)$ Using synthetic detergents for washing clothes	$(3)$ Damage to the ozone layer
$(D)$ Releasing smoke from vehicles and factories into the atmosphere.	$(4)$ Neurological disorders in humans.
$(E)$ Using chlorofluorocarbon compounds to clean computer parts.	$(5)$ Classical smog,acid rain,water pollution,respiratory problems,damage to buildings,metal corrosion.

The water quality of a pond was analysed and its $BOD$ was found to be $4$. The pond has