Answer:
Option (D)
Step-by-step explanation:
Carbon dioxide is an important greenhouse gas. It is currently about 0.03% of CO₂ by volume and plays a significant role in controlling the earth's average temperature. A small increase in the amount of CO₂ can lead to an increase in global temperature.
Since 1750, the concentration of CO₂ has been constantly increasing due to the industrial revolution. The number of factories and industries has been set up, as a result of which a huge amount of toxic gases has been released into the atmosphere, thereby leading to the increase in the average earth's temperature.
Thus, according to the statistical data, CO₂ content has increased up to approximately 40%
Thus, the correct answer is option (D).