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.

Ex Input:
A student notices a paw print while walking in a park. The paw print could be considered a fossil if the print was in ___.  
 (A) rock (B) topsoil (C) thick mud (D) loose sand

Ex Output:
A


Ex Input:
Parents with freckles often have children with freckles. This occurs because  
 (A) freckles develop from light. (B) certain foods cause freckles. (C) certain habits cause freckles. (D) freckles are an inherited trait.

Ex Output:
D


Ex Input:
Which is the most cooperative relationship between species?  
 (A) mutualism (B) predation (C) parasitism (D) coexistence

Ex Output:

A