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").

[EX Q]: How does erosion impact a river? (A) enlargening (B) warming (C) heightening (D) shrinking
[EX A]: A

[EX Q]: In May I have a black cat what might I be unable to wear? (A) dark purple (B) yellow (C) dark grey (D) black
[EX A]: B

[EX Q]: Milk sold in supermarkets is pasteurized because (A) all raw milk is safe (B) to keep bacteria from getting into the milk after the customer buys it (C) the factory farmed cows produce a lot of pus in their milk (D) that makes it taste better
[EX A]:
B