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: Which type of organism is at the lowest level of the food chain?  
 (A) autotroph (B) heterotroph (C) carnivore (D) omnivore
Example Output: A

Example Input: Which statement describes all matter?  
 (A) All matter contains carbon. (B) All matter contains oxygen. (C) All matter is made up of cells. (D) All matter is made up of atoms.
Example Output: D

Example Input: Which process allows green plants to control the amount of water stored in their leaves?  
 (A) photosynthesis (B) condensation (C) respiration (D) transpiration
Example Output:
D