Which substance should have its atmospheric concentrations reduced in

order to return acid rain to rain's normal pH?

A. CFCs

B. Sulfur

C. Water

D. Phosphorous

B. Sulfur

Explanation:

Acid rain is the result of sulfur dioxide emissions combined with nitroxen oxides. This occurs when both compounds interact with water and oxygen (and other molecules) that are already present in the atmosphere.

This phenomenon is extremely dangerous for both humans, fauna, and flora, especially when it comes to aquatic organisms. Some freshwater fish species, for instance, are not able to grow or develop due to the increased pH. In other cases, when the pH is even lower, organisms are not able to cope and eventually die.

Therefore, a reduction in atmospheric concentrations of sulfure could reduce acid rain and return rain to its normal pH.