In this task, you are given a multiple-choice question and you have to pick the correct option. Answer with option indexes (i.e., "A", "B", "C", and "D").

Example Input: A light is refracted when (A) it shines at a gem (B) it shines at a mirror (C) it reflects off a spoon (D) it reflects off a car
Example Output: A

Example Input: Humans contribute to environmental pollution (A) by purchasing products made from recycled products (B) by switching to energy efficient appliances (C) by leaving behind refuse on public beaches (D) by frequently recycling paper and plastic
Example Output: C

Example Input: An animal is likely to be negatively impacted by food with (A) animals (B) fungi (C) water (D) plants
Example Output:
B