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: Mineral graphite can pierce the skin surface. 
Question: What can pierce the skin surface?
Mineral graphite.

Fact: Viruses often infect something killed by antibiotics. 
Question: Viruses often infect something killed by what?
Antibiotics.

Fact: bears require stamina to succeed at physical activities. 
Question: What requires stamina to succeed at physical activities?

bears.