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: Which *** of a *** is an *** *** *** to *** ***?  (A) cleaning its ears (B) sleeping on a chair (C) sharpening its claws (D) meowing when it is hungr.

Ex Output:
E.


Ex Input:
Question: The invention of the *** allowed which of the following to take place?  (A) the discovery of cells (B) the identification of weather patterns (C) detailed observation of planets (D) communication between distant citie.

Ex Output:
E.


Ex Input:
Question: An influence that can change the motion of an object, such as its speed or direction, is called ___.  (A) solubility (B) buoyancy (C) force (D) potential energ.

Ex Output:

C.