Q: You are given a science question (hard-level) and four answer options (associated with "A", "B", "C", "D"). Your task is to find the correct answer based on scientific facts, knowledge, and reasoning. Do not generate anything else apart from one of the following characters: 'A', 'B, 'C', 'D'. There is only one correct answer for each question.
In a series of chemical reactions, XYZA, X converts to Y, Y converts to Z, and Z converts to A. Which term describes the process if the production of A interferes with the conversion of X to Y?
(A) a complimentary response (B) a control system (C) negative feedback (D) positive feedback
A:
C