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 Q]: Which of these is a nonliving part of a forest?  
 (A) Tree (B) Soil (C) Worm (D) Mushroom
[EX A]: B

[EX Q]: Which scientist is known for his genetics experiments with pea plants?  
 (A) Charles Darwin (B) Gregor Mendel (C) Carolus Linnaeus (D) Robert Hooke
[EX A]: B

[EX Q]: When heat flows from a hot spot to a cooler spot, entropy increases. When heat is forced to flow from a cool spot to a warmer spot, entropy decreases. Marta is looking for something in her house that causes a decrease in entropy. Which of these should she choose?  
 (A) an ice cube melting (B) the refrigerator (C) an egg frying (D) the toaster
[EX A]:
B