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.

Example Input: Fact: x-rays are used in oncology. 
Question: what are used in oncology?
Example Output: x-rays.

Example Input: Fact: Breathing provides one substance transported by the blood. 
Question: What process provides one substance transported by the blood?
Example Output: breathing.

Example Input: Fact: hydropower requires devastating a river. 
Question: what does hydropower require doing to a river?
Example Output:
devastating it.