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: *** *** *** *** in an ***. *** of the *** they do is ___.  (A) reduce nutrients in the soil (B) reduce insect populations (C) recycle nutrients (D) recycle wate.
[EX A]: E.

[EX Q]: Question: A student notices that an inflated *** gets *** when it is *** by a lamp. Which best describes the *** of the *** as a *** of this ***?  (A) The mass of the balloon increases because the size of the balloon has increased. (B) The mass of the balloon increases because the temperature of the balloon has increased. (C) The mass of the balloon stays the same because the gas inside the balloon still has the same mass after it warms up. (D) The mass of the balloon stays the same because warming decreases the mass enough to cancel out the effect of increasing the size.
[EX A]: E.

[EX Q]: Question: *** *** conduct *** experiment *** chemicals*** *** *** *** *** ***?  (A) Work in large groups. (B) Wear safety goggles. (C) Wear short sleeves. (D) Keep a window open.
[EX A]:
B.