TASK DEFINITION: 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.
PROBLEM: What is the function of the nucleus in a cell?  
 (A) provides energy (B) provides nutrients (C) controls activity (D) controls movement

SOLUTION: C

PROBLEM: When a cup of water at room temperature is put in a freezer, the water's state of matter will change from  
 (A) liquid to gas (B) gas to liquid (C) liquid to solid (D) solid to liquid

SOLUTION: C

PROBLEM: The organisms that convert solar energy and raw materials into food are  
 (A) producers. (B) consumers. (C) herbivores. (D) decomposers.

SOLUTION:
A