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]: In the desert it was harder to find a (A) stream (B) cactus (C) dry bed (D) canyon
[EX A]: A

[EX Q]: If something is in an ecosystem, it could be (A) invisible (B) vacuum of space (C) lacking life (D) alien
[EX A]: C

[EX Q]: When a wildfire happens what catches fire? (A) rocks (B) timberland (C) water (D) rivers
[EX A]:
B