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'.

[EX Q]: Question: Members of a planning team build a *** of a nearby *** and then block the *** to show how it can *** a lake. Which is a *** of the model?  (A) showing how a nearby town will avoid flooding (B) explaining how the lake will be used for recreation (C) explaining how some of the water can be used for agriculture (D) showing how the dam will affect the plants and animals in the are.
[EX A]: E.

[EX Q]: Question: *** precaution *** *** *** *** *** *** *** observations *** *** Sun?  (A) Use only new equipment. (B) Use a very strong telescope. (C) Project image onto a piece of cardboard. (D) Look at the Sun only in the morning.
[EX A]: C.

[EX Q]: Question: A student wants to look under a heavy ***. Which *** *** would be *** to use to *** the ***?  (A) Wheel and axle (B) Lever (C) Inclined plane (D) Scre.
[EX A]:
B.