Given the task definition, example input & output, solve the new input case.
You are given a science question (easy-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.
Example: Which part of a bicycle BEST moves in a circle? 
 (A) Seat (B) Frame (C) Foot pedal (D) Kickstand
Output: C
Seat, frame and Kickstand are static parts of the bicycle, even when bicycle moves. Foot pedal moves in a circle as bicycle moves.

New input case for you: Specialized cells protect the human body from disease-causing microbes by  
 (A) producing chemicals that destroy the microbes (B) dissolving wastes from the microbes (C) creating recessive genes in the microbes (D) supplying oxygen and nutrients to the microbes
Output:

Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
user
A