instruction:
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: marine and benthic creatures lack respiratory and excretory systems. 
Question: what creatures lack respiratory and excretory systems?
answer:
marine and benthic.


question:
Fact: humans require energy for growth. 
Question: what requires energy for growth?
answer:
humans.


question:
Fact: Lack of saliva hinders the break down of food into components the body can absorb. 
Question: Lack of which of the following can hinder the break down of food in the body?
answer:

saliva.