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 Input: In animal skin tissue, cell division is responsible for  
 (A) growth and repair (B) sexual reproduction (C) obtaining energy (D) production of sex cells
Example Output: A

Example Input: Bridge inspectors have determined that a bridge is unsafe. Which of the following is the BEST design process the company should use to correct the problem?  
 (A) identify the problem-repair the bridge-plan for the repair (B) plan for the repair-repair the bridge-identify the problem (C) plan for the repair-identify the problem-repair the bridge (D) identify the problem-plan for the repair-repair the bridge
Example Output: D

Example Input: Fossil records indicate that Earth was first inhabited by bacteria-like organisms. These organisms  
 (A) were single-celled. (B) had organ systems. (C) were multi-cellular. (D) had small appendages.
Example Output:
A