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.
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Question: A population of ground squirrels has established a community in the grasslands of the Great Plains. Temperatures often reach -15°C for most of the winter. What is the most likely behavior the ground squirrels use to survive these winter temperatures?  
 (A) burrowing below the frost point of the soil surface (B) burrowing in tree trunks above the soil surface (C) consuming roots found under the soil surface (D) consuming organisms found in the soil surface

Answer: A


Question: An object such as a hammer weighs less on the Moon than on Earth. This is because the Moon has a  
 (A) thinner atmosphere than Earth. (B) smaller diameter than Earth. (C) stronger magnetic field than Earth. (D) lower mass than Earth.

Answer: D


Question: Which trait is common in gases that contribute to Earth's greenhouse effect?  
 (A) the ability to trap heat (B) a tendency to lose electrons (C) a tendency to exist as diatomic molecules (D) the ability to bond with multiple other elements

Answer:
A