Given the task definition and input, reply with output. 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").

The planet that contains many ecosystems is sequentially _________ from the center of its solar system (A) fifth (B) first (C) third (D) fourth

C
Given the task definition and input, reply with output. 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").

The planet that contains many ecosystems is sequentially _________ from the center of its solar system (A) fifth (B) first (C) third (D) fourth

user
C
assistant
Given the task definition and input, reply with output. 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").

The planet that contains many ecosystems is sequentially _________ from the center of its solar system (A) fifth (B) first (C) third (D) fourth

C