TASK DEFINITION: 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.
PROBLEM: Lichens are symbiotic organisms made of green algae and fungi. What do the green algae supply to the fungi in this symbiotic relationship?
(A) carbon dioxide (B) food (C) protection (D) water

SOLUTION: B

PROBLEM: In the morning, students observed puddles of water all over the playground. What would best explain why the playground was dry in the afternoon?
(A) Animals drank the water. (B) The wind stopped blowing. (C) Someone dried the puddles. (D) The water evaporated during the day.

SOLUTION: D

PROBLEM: A student flips a coin four times. It lands "heads" up three times. The student concludes that the coin will land "heads" up three times out of four. What will make the conclusion more accurate?
(A) substituting a different coin (B) flipping the coin twenty more times (C) taping a weight to one side of the coin (D) flipping the coin over a smoother surface

SOLUTION:
B