Definition: You are given a question on clinical knowledge. You are also given 4 answer options (associated with "A", "B", "C", "D"), out of which only one is correct. You need to answer the question by selecting the correct option. You should only answer with the choice letter, not the whole answer.
Input: A muscle fibre relaxes when:
(A)the nerve stimulus is removed. (B)the nerve stimulus is too forceful. (C)the actin binding sites are uncovered. (D)the actin binding sites are saturated.

A