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: An automobile engine works by summing kinetic energy and potential energy. 
Question: What works by summing kinetic energy and potential energy?
[A]: an automobile engine.


[Q]: Fact: Hawks have an increased population size. 
Question: What has an increased population size?
[A]: Hawks.


[Q]: Fact: Something that prevents chlamydia can break. 
Question: Something that prevents what can break?
[A]:
Chlamydia.