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: passive immunity lasts only as long as the antibodies survive in blood. 
Question: passive immunity lasts only as long as the antibodies survive where?
blood.

Fact: the amount of precipitation depends on condensation. 
Question: What does precipitation depend on?
condensation.

Fact: lack of certain hormones in the blood can cause impotence. 
Question: Lack of what in the blood can lead to impotence?

hormones.