instruction:
In this task, you need to answer basic science questions. For each question, several terms are intentionally masked with ***. This masking can cover very few or many of the question words. Clearly, if masked terms are important, the modified question will be impossible to answer. Please indicate the correct answer with one of the following responses: "A", "B", "C", "D" or "E". While "A"-"D" correspond to the answer options provided in the input, "E" represents "I don't know" for questions that do not provide enough information. Respond via "E" if the question is not answerable. Do not generate anything else apart from one of the following characters: 'A', 'B, 'C', 'D', 'E'.
question:
Question: What is the main source of *** *** on Earth?  (A) fire (B) volcanoes (C) the sun (D) electricit.
answer:
C.


question:
Question: Wind is a natural resource that benefits the southeastern shore of the Chesapeake Bay. How could these winds best benefit humans?  (A) The winds could blow oil spills into the bay. (B) The winds could be converted to fossil fuel. (C) The winds could blow air pollution toward land. (D) The winds could be converted to electrical energy.
answer:
D.


question:
Question: Which *** help to destroy pathogens such as bacteria that enter the human body?  (A) red blood cells (B) liver cells (C) white blood cells (D) brain cell.
answer:

C.