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: What becomes smoother through weathering? (A) rainbow (B) water (C) cat (D) pumice
Example Output: D

Example Input: Photosynthesis features (A) single celled organisms (B) humans (C) cats (D) fish
Example Output: A

Example Input: Plants may use leaves, especially waxy ones, in order to (A) create a way to grow (B) collect and hold on to dampness (C) store food for themselves (D) water themselves in droughts
Example Output:
B