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: Scientists have studied the specific stages in the life cycle of stars. In which stage do stars spend most of their lifetime?  
 (A) red giant (B) black dwarf (C) white dwarf (D) main sequence

A: D
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Q: In which of these organs does most absorption of nutrients take place?  
 (A) liver (B) stomach (C) small intestine (D) large intestine

A: C
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Q: Evan is performing an investigation. Before conducting his investigation, what must Evan do?  
 (A) record his observations (B) develop a hypothesis (C) reach a conclusion (D) organize the data

A:
B
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