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]: There is a river at the base of Mount Tom. In the spring the water level is usually very high. In the summer it is lower. The higher level of water during the spring comes from  
 (A) hurricanes. (B) melting snow. (C) tornadoes. (D) evaporating water.
[EX A]: B

[EX Q]: A student was taking notes while the teacher was discussing cells. Which of these is a statement that the teacher most likely made?  
 (A) Most cells have the same shape. (B) The shape of a cell depends upon its function. (C) Cells that carry information are round and disk-shaped. (D) Blood cells that move through the body are long and thread-like.
[EX A]: B

[EX Q]: Termites eat wood but cannot digest it. Protozoans live in the termites' stomachs and use enzymes to break down the wood. The digested wood provides nutrition for both the termites and the protozoans. What type of relationship is this?  
 (A) mutualism (B) parasitism (C) predation (D) commensalism
[EX A]:
A