Given the question: You are presented with the question "What has a negative impact on water quality?" and the following answer choices: - rain - harmful substances - rain below 5.6 pH - sleet - fossil fuels - Burning fuel and air - snow - decaying trees Now knowing that acid rain has a negative impact on water quality and acid rain has a pH below 5.6, choose the best answer.
The answer is:
rain below 5.6 pH