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.
--------
Question: Fact: the key cells involved in the immune response are produced in the bone marrow. 
Question: where are the key cells involved in the immune response produced in?

Answer: bone marrow.


Question: Fact: killing microorganism in food is important to food safety. 
Question: killing microorganisms in food is important to?

Answer: food safety.


Question: Fact: Protection and humidity is important for plants. 
Question: What are two things that are important for plants?

Answer:
Humidity and protection.