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: A leaf is covered in mud during a landslide. After one million years, this leaf will most likely be ___.  
 (A) a fossil (B) an animal species (C) a new plant species (D) a nonrenewable fuel
Example Output: A

Example Input: A scientist uses angstrom units to measure the distance between two points. The scientist is most likely measuring the distance between two  
 (A) atoms. (B) cities. (C) continents. (D) stars.
Example Output: A

Example Input: A student made observations of four rock samples. Which of these observations most likely describes a sedimentary rock?  
 (A) Sample 1 has bands of light and dark crystals. (B) Sample 2 has pink, gray, and white crystals grown together. (C) Sample 3 is made up of one huge, pale pink crystal. (D) Sample 4 is made up of layers of sand grains cemented together.
Example Output:
D