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: The population of rabbits in an area increases. That could have been caused by (A) More predators have been moving into the area (B) The rabbits are becoming infertile (C) Hunters are trapping the rabbits (D) More precipitation falling lately
Example Output: D

Example Input: Every 1440 minutes (A) the moon is full (B) there's a lunar eclipse (C) a new year starts (D) the sun sets in the west
Example Output: D

Example Input: a closed circuit (A) is turned off (B) is uninterrupted (C) has multiple paths (D) incomplete
Example Output:
B