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]: The first telescopes were invented hundreds of years ago. Which was discovered as a result of this invention?  
 (A) the moons of Jupiter (B) the bacteria that causes disease (C) the deep-sea trenches in the ocean (D) the parts of a plant that perform photosynthesis
[EX A]: A

[EX Q]: Which object is best used to demonstrate the bending of light as it passes through a substance?  
 (A) convex lens (B) flat mirror (C) opaque rod (D) concave mirror
[EX A]: A

[EX Q]: Some microorganisms cause human disease. Other microorganisms are used in making cheese, yogurt, and bread. Based on this information, the relationship between humans and microorganisms can be  
 (A) beneficial, only (B) harmful, only (C) beneficial or harmful
[EX A]:
C