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: Organisms with only one cell (A) are prohibited from specializing (B) can freely specialize openly (C) are unsure what specializing is (D) learn how to specialize
Example Output: A

Example Input: Which event can lead to the human caused change of an environment? (A) seasonal storms (B) annual flooding (C) natural woodland fires (D) clear cutting
Example Output: D

Example Input: When would a puddle get smaller and disappear the fastest? (A) on a snowy day (B) on a day without clouds (C) on a cloudy day (D) on a dark day
Example Output:
B