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.

[EX 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
[EX A]: D

[EX Q]: Which location on Earth receives the most direct sunlight?  
 (A) the deserts (B) the South Pole (C) the equator (D) the Western Hemisphere
[EX A]: C

[EX Q]: In what type of rock would a geologist most likely find evidence of ancient life?  
 (A) sedimentary (B) foliated (C) metamorphic (D) volcanic
[EX A]:
A