instruction:
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.
question:
Which of the following statements best explains why earthquakes occur more frequently in California than in Massachusetts?
(A) The rock found in California is igneous, but the rock found in Massachusetts is sedimentary. (B) California is located on the boundary of two crustal plates, but Massachusetts is not. (C) The rock under California is soft, but the rock under Massachusetts is hard. (D) California is located on a continental plate, but Massachusetts is not.
answer:
B

question:
Wolves have adapted skills for hunting large hoofed animals such as elk, deer, or moose. Wolves tend to target prey animals that are sick or weak. The wolf benefits from this strategy because it uses less energy to hunt. How would the prey animal population also benefit from this strategy?
(A) by promoting detrimental genes (B) by stimulating beneficial DNA mutations (C) by preventing the introduction of other predator species (D) by increasing the reproductive success of healthy prey animals
answer:
D

question:
Which statement best describes how the circulatory system and respiratory system can work together?
(A) Toxins are removed from the bloodstream by the liver. (B) The stomach signals for the production of gastric juices. (C) Food molecules are transported to the organs of the body. (D) Gases are exchanged between the lungs and blood vessels.
answer:
D