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.

[Q]: Fact: Any surface that has not been sterilized will produce substances that are toxic. 
Question: What will produce substances that are toxic?
[A]: a surface not sterilized.


[Q]: Fact: An animal requires oxygen for survival. 
Question: What does an animal need for survival?
[A]: Oxygen.


[Q]: Fact: wolves hunt by sensing light. 
Question: How do wolves hunt?
[A]:
Sensing light.