In this task, you are given two facts, and a multiple-choice question. Based on the given facts, answer the question with index of the correct option (e.g, "A").
Q: Fact1: pollutants have a negative impact on the environment, Fact2: Carbon dioxide is a pollutant., Question: What affects the environment negatively? (A) sunlight (B) normal weather patterns (C) carbon dioxide (D) cigarettes (E) positivity (F) Smoking (G) harmful substances (H) fossil fuels
A:
C