Which of the following gases is primarily associated with contributing to acid rain?

The gas that is primarily associated with contributing to acid rain is sulfur dioxide. When sulfur dioxide is released into the atmosphere, typically from the burning of fossil fuels and industrial processes, it reacts with water vapor and oxygen to form sulfuric acid. This sulfuric acid can then fall to the ground in precipitation, which is known as acid rain.

Acid rain can have detrimental effects on the environment, including harming aquatic ecosystems, damaging soil, and negatively impacting plant life. The presence of sulfur dioxide in the atmosphere is a significant factor in the overall quality of environmental health, particularly related to air and water quality.

While carbon dioxide does contribute to greenhouse gas effects and methane is also a potent greenhouse gas, neither of them directly contributes to acid rain formation. Ammonia, while it can participate in atmospheric chemistry, does not play the same central role as sulfur dioxide in the context of acid rain specifically. Thus, sulfur dioxide is recognized as the main gas responsible for the phenomenon of acid rain.