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: In order to maintain good health, humans should  
 (A) eat foods high in fat (B) exercise regularly (C) drink alcohol often (D) smoke tobacco occasionally

SOLUTION: B

PROBLEM: The number of fish in a lake suddenly increases. How will the increase most likely affect the lake?  
 (A) There will be less water in the lake. (B) More plants will grow in the lake. (C) More frogs will live in the lake. (D) There will be fewer insects in the lake.

SOLUTION: D

PROBLEM: Which information does a student need to differentiate between the speed and the velocity of a vehicle in motion?  
 (A) the rate of the motion (B) the direction of the motion (C) the change in the amount of motion (D) the amount of distance traveled during motion

SOLUTION:
B