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 Input:
Pollution is (A) throwing a gum wrapper in the ocean (B) trees in a forest (C) Fish swimming in the sea (D) The wind carrying seeds

Ex Output:
A


Ex Input:
A light is refracted when (A) it shines at a gem (B) it shines at a mirror (C) it reflects off a spoon (D) it reflects off a car

Ex Output:
A


Ex Input:
A car can be powered by all but (A) the push of a cat (B) fossil fuel products refined (C) the motion of atmosphere (D) the warmth of the sun

Ex Output:

A