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: A scientist uses angstrom units to measure the distance between two points. The scientist is most likely measuring the distance between two  
 (A) atoms. (B) cities. (C) continents. (D) stars.

A: A
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Q: Which physical structure would best help a bear to survive a winter in New York State?  
 (A) big ears (B) black nose (C) thick fur (D) brown eyes

A: C
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Q: Some butterflies live an average of two weeks. This period of time is called a life  
 (A) process (B) span (C) change (D) cycle

A:
B
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