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: One important use of coal is to produce energy for homes. Coal can be burned and converted to  
 (A) wind energy. (B) nuclear energy. (C) electrical energy. (D) solar energy.

Answer: C


Question: Oxygen reacts with iron to produce rust and with hydrogen to produce water. Which statement describes both reactions?  
 (A) A different mixture is formed in each case. (B) A different solution is formed in each case. (C) Both a change of state and of elements is involved. (D) New molecules are formed but the same elements exist.

Answer: D


Question: Farm fertilizers are often carried by runoff into the Mississippi River and down to the Gulf of Mexico, resulting in algae blooms. Which of these results from the decomposition of the algae blooms?  
 (A) an abundance of dissolved oxygen (B) dead zones where there are no fish (C) a reduction in atmospheric carbon dioxide (D) food webs with rapidly growing populations

Answer:
B