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: An example of an acquired characteristic is (A) the thickness of a horse's mane (B) the length of a horse's mane (C) the number of legs a horse has (D) the color of a horse's mane
Example Output: B

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: Lucy left a pan half full of water in the sun and it dried up in one afternoon. (A) the pan was in the cool shade (B) a squirrel dumped the water of its head to cool off (C) butterflies drank it all (D) it was the summertime
Example Output:
D