Question

24. The increase in the proportion of ______ in air leads to global warming.

• A. $\mathrm{CO}$
• B. ${\mathrm{CO}}_2$
• C. ${\mathrm{SO}}_2$
• D. ${\mathrm{N}}_2$

Answer 1

The correct option is B

${\mathrm{CO}}_2$

Explanation for correct option:

Option (B):

• Global warming results in a gradual increase in the temperature of the earth's surface. The main cause of global warming is the increase in air pollutants.
• Carbon dioxide $\left({\mathrm{CO}}_2\right)$ is the main contributor to global warming.

Explanation for incorrect options:

Option (A): Carbon monoxide $\mathrm{CO}$ is a very poisonous gas and is produced by incomplete combustion of fuels.

Option (C): Sulphur dioxide ${\mathrm{SO}}_2$ gas causes acid rain. It is released from factories, burning of fossil fuels, etc.

Option (D): Nitrogen ${\mathrm{N}}_2$ is the major component of air and it is a chemically unreactive gas.

Hence, option (B) is the correct answer. The increase in the proportion of ${\mathrm{CO}}_2$ air leads to global warming.