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 teacher heats a pot of water. Once the water reaches 100°C, which point has the water reached?  
 (A) boiling (B) melting (C) freezing (D) evaporating

A: A
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Q: Which example would result in new cells that are most different from the parent cells?  
 (A) yeast cells splitting into new cells (B) bacteria cells dividing into new cells (C) skin cells dividing to produce more skin cells (D) sperm and egg cells uniting to produce fertilized egg cells

A: D
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Q: Some birds fly south in the fall and return in the spring. This is an example of  
 (A) migration (B) camouflage (C) hibernation (D) growth

A:
A
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