TASK DEFINITION: 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").
PROBLEM: the presence of which of these is required for the formation of cavernous chambers? (A) some carbonated soda (B) some carbon dioxide (C) some carbonic acid (D) carbon monoxide gas

SOLUTION: C

PROBLEM: A person in a suit near a sunken ship is sprayed in the face with a dark substance by (A) a cephalopod (B) a bear (C) a hose (D) a pencil

SOLUTION: A

PROBLEM: A man wants to create a room that he can light up with the flick of a switch. To do this, he sends some electricity into a completed electrical circuit, through a conductor, which allows (A) light from the sun to shine (B) lights to be burned out (C) sunlight to shine through bulbs (D) his plan to succeed

SOLUTION:
D