Residents in a city most concerned about acid rain would likely want to improve which water quality parameter?

Acid rain is characterized by precipitation that contains elevated levels of sulfuric and nitric acids, resulting from atmospheric pollution. This process leads to a decrease in the pH of rainwater, making it more acidic. When considering water quality parameters that residents concerned about acid rain would want to improve, a higher pH level (meaning a less acidic environment) is crucial.

Improving the pH level means reducing acidity in water bodies, which can help mitigate the harmful effects of acid rain, such as damage to aquatic life and ecosystems, as well as infrastructure. A higher pH supports a more balanced and healthy aquatic environment, fostering the growth of organisms that might be adversely affected by lower pH levels.

In contrast, increased dissolved oxygen levels, lower bacteria counts, and reduced nutrient levels, although important for overall water quality, do not directly address the primary concern of acid rain and its impact on pH. Thus, focusing on decreasing acidic conditions (or increasing pH) is essential for residents worried about acid rain.