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.

Fact: Blood feeders can enter the host through the skin. 
Question: What can enter a host through the skin?
Blood feeders.

Fact: CPU time can be used as a clock. 
Question: What computer component can you use to measure time?
CPU.

Fact: creatures that can swim have a centralized nervous system with a brain. 
Question: What that can swim have a centralized nervous system with a brain?

creatures.