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").

Input: Consider Input: This can be used to light up a light bulb (A) grass (B) dirt (C) stones. (D) biofuel

Output: D


Input: Consider Input: Which is the least massive? (A) the Earth (B) the moon (C) the sun (D) the solar system

Output: B


Input: Consider Input: A person can create the most friction by rolling a ball over (A) glass (B) gravel (C) ice (D) marble


Output: B