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: Beavers cause ponds and lakes to form. 
Question: What can be the cause of lakes and ponds forming?

Output: beavers.


Input: Consider Input: Fact: DNA messages to proteins are manufactured by RNA. 
Question: DNA messages to proteins are manufactured by what?

Output: RNA.


Input: Consider Input: Fact: segmented animals can have closed circulatory systems. 
Question: what kind of circulatory system can some segmented animals have?


Output: closed.