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 of the following forms of energy is released or absorbed in most chemical reactions?      
 (A) light energy (B) electrical energy (C) sound energy (D) heat energy
Example Output: D

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: An object has a weight of 10 kg on the surface of Earth. If the same object were transported to the surface of Mars, the object would have a weight of 3.8 kg. Which best explains why the weight of the object changed when transported from Earth to Mars?  
 (A) The density of the object is greater on Earth than it is on Mars. (B) The volume of the object is greater on Earth than it is on Mars. (C) Gravitational force is greater on Earth than it is on Mars. (D) Atmospheric pressure is less on Earth than it is on Mars.
Example Output:
C