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").

Example Input: The earth makes its way around the sun. Because of the constant rotation, the appearance of these is unlikely to be regular. (A) the moon (B) the oceans (C) celestial bodies (D) the sun
Example Output: C

Example Input: insulation for the purposes of moving electrons involves (A) conductor wrapped wire (B) insulator wrapped insulator (C) non coated metal (D) insulation encompassed wire
Example Output: D

Example Input: What becomes smoother through weathering? (A) rainbow (B) water (C) cat (D) pumice
Example Output:
D