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: How can it be shown that an electrical conductor is a vehicle for the flow of electricity? (A) holding an electrified fence can kill you (B) electricity is unable to conduct well through rubber shoe soles (C) sticking a fork into an electrical outlet is safe if it is plastic (D) electricity is a volatile thing
Example Output: A

Example Input: Which would create the most pollution (A) animals (B) rivers (C) smoke stacks (D) toxicity
Example Output: C

Example Input: Which would most directly benefit from installing receptors for converting light into power? (A) a family of humans in a city where it rains every day (B) a herd of crows (C) a research base near the equator (D) a group of squirrels
Example Output:
C