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: Mammals generate heat mainly by burning calories. 
Question: Mammals generate heat mainly by what?
[A]: burning calories.


[Q]: Fact: Repellents can stop harm caused by flea bites. 
Question: How can you prevent harm caused by flea bites?
[A]: Using repellent.


[Q]: Fact: Plants have specialized reproductive tissues. 
Question: Plants have specialized tissues for what?
[A]:
reproduction.