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.

Q: The pull of gravity from Earth has the greatest effect on  
 (A) comets. (B) the Sun. (C) asteroids. (D) the Moon.

A: D
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Q: In Maryland, most bears have thick, dark fur. Which statement best explains how dark fur helps bears survive in the forests of Maryland?  
 (A) Dark fur is lightweight. (B) Dark fur scares enemies. (C) Dark fur helps bears hide. (D) Dark fur keeps bears cool.

A: C
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Q: Which rankings of trees would most likely useful in a scientific study of fruit production in apple trees?  
 (A) date of flowering and the fruit yield (B) fruit yield and taste of the fruit (C) taste of the fruit and smell of the flower (D) date of flowering and smell of the flower

A:
A
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