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]: Which likely increased atmospheric CO2 recently? (A) sustainable fisheries (B) electric cars (C) motorcycles (D) ant populations
[EX A]: C

[EX Q]: Riding a two wheeled human powered vehicle is good for the environment because (A) it runs without fuel (B) it helps people stay in shape (C) they are cheaper to maintain (D) they are more fun to drive
[EX A]: A

[EX Q]: As a source of light moves directly overhead of an object , what happens to it's shadow (A) the object will get brighter (B) the shadow will start to spin (C) the size will decrease (D) the light will lean to one side
[EX A]:
C