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 Input:
Question: A student is looking at insects using a *** ***. What about the insects can best be seen with the *** ***?  (A) different colors of insect bodies (B) how insects protect themselves (C) type of eyes insects have (D) size of the insect.

Ex Output:
E.


Ex Input:
Question: The systems of the human body work together. Which *** works with the *** *** by pulling on the bones to create ***?  (A) digestive (B) circulatory (C) muscular (D) nervou.

Ex Output:
C.


Ex Input:
Question: A student notices that an *** *** gets *** when it is *** by a ***. Which best *** 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 Output:

E.