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: Researchers are developing new types of crop plants with desirable characteristics such as disease resistance and drought tolerance. Crossing plants so that the next generation will express desirable traits is best described as  
 (A) selective breeding. (B) natural selection. (C) genetic engineering. (D) gene sequencing.

Answer: A


Question: A geologist finds a layer of shale near the surface from a certain time period. Nearby, the geologist finds the same layer of shale, but it is deeper underground than the first layer. What might have caused the difference in the depth of the shale layer?  
 (A) a meteorite (B) a fault (C) ancient fossils (D) animal life

Answer: B


Question: Riding a bicycle produces several forms of energy. Which form of energy is produced in the greatest amount by pedaling a bicycle down the sidewalk?  
 (A) chemical (B) radiant (C) kinetic (D) sound

Answer:
C