FOR WHICH OF THE FOLLOWING REASONS CAN NATURAL POLLUTANTS PLAY...

Câu 63. For which of the following reasons can natural pollutants play an important role in controlling air

pollution?

A.They occur in greater quantities than other pollutants.

B. They function as part of a purification process.

C. They are less harmful to living beings than other pollutants.

D. They have existed since the Earth developed.