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]: What does gravity cause substances on a planet? (A) things to move sideways (B) things to be moved upwards (C) things to descend to the lowest surface possible (D) things to stay in the same place
[EX A]: C

[EX Q]: if the surface of our planet is different after a while, what could have happened? (A) the surface eroded on its own (B) all of these (C) there were natural occurrences (D) man has damaged the surface
[EX A]: B

[EX Q]: Who'd be able to see a rose is pink at night? (A) rocks (B) the Rio Grande (C) a beeping sound (D) lemurs
[EX A]:
D