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: Amphibians undergo changes in structure of being in that (A) salamanders can regrow their tails (B) salamanders can lose their tails (C) frogs can breathe air and water (D) they begin as a different looking being
Example Output: D

Example Input: A learned characteristic could be (A) Eye color (B) a cartwheel (C) freckles (D) Hair color
Example Output: B

Example Input: What is a source of nectar? (A) daffodils (B) flower toys (C) sunlight (D) groundwater
Example Output:
A