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 filament that is in a glass container will be this when a switch is flipped to cause glass to glow: (A) dark (B) toasty (C) cold (D) icy
Example Output: B

Example Input: You can use what to fake sunlight for plants? (A) love (B) a flash light (C) breathing (D) water
Example Output: B

Example Input: How essential is air for animals? (A) it is optional (B) it is necessary (C) it is useless (D) it is unknown
Example Output:
B