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: Russell wants to observe changes in nature over the next few months. What can a thermometer help Russell investigate?  
 (A) rainfall amounts each week (B) tiny organisms in pond water (C) the high temperatures each day (D) the amount of growth in a plant

SOLUTION: C

PROBLEM: What happens at the boiling point of a substance?  
 (A) liquid becomes a gas (B) solid becomes a gas (C) liquid becomes a solid (D) solid becomes a liquid

SOLUTION: A

PROBLEM: Many cities encourage people to recycle. The items that can be recycled are placed in a special container and picked up each week from people's homes. How does recycling most likely help the environment?  
 (A) Recycling reduces littering. (B) Recycling makes products last longer. (C) Recycling puts less trash in the city landfill. (D) Recycling increases the amount of dust in the air.

SOLUTION:
C