In this subtask, you will answer a simple science question. Please indicate the correct answer. If you're not sure about the answer, choose the last option "I don't know". Do not generate anything else apart from one of the following characters: 'A', 'B, 'C', 'D', 'E'. The "A"-"D" responses correspond to the answer options mentioned in the input. There is a 5th option "E" which should be used for questions for which you're not sure about the answer (e.g., when the questions do not provide enough information to answer).

Example Input: Question: Devices must be used to prevent electrical energy from being converted to heat energy. Which of the following devices are used to prevent too much electrical current from overloading a circuit and causing a fire?  (A) fuse (B) electromagnet (C) coil (D) generato?
Example Output: A.

Example Input: Question: Which of the following animals is an invertebrate?  (A) Squirrel (B) Sea gull (C) Cricket (D) Lizar?
Example Output: C.

Example Input: Question: What do plants use as input for photosynthesis?  (A) carbon dioxide (B) oxygen (C) minerals (D) nitroge?
Example Output:
A.