Write a correct answer to the given question based on its associated fact. Make sure that your answer is contained in the associated fact. Don't be creative and introduce any new word that is not mentioned in the associated fact! Remember that the associated fact has been rearranged to form the question. So, the correct answer words must lie within the associated fact. The correct answer can be a word, phrase, or even a sentence.

Input: Consider Input: Fact: plants are sensitive to darkness. 
Question: What are plants sensitive to?

Output: darkness.


Input: Consider Input: Fact: The pituitary gland regulates the metabolic rate in the body. 
Question: What gland helps regulate the metabolic rate in the body?

Output: Pituitary gland.


Input: Consider Input: Fact: mammals have a layer of food under their skin to help insulate the body. 
Question: What do mammals have under their skin that is used to insulate the body?


Output: food.