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: Roots will decay is the conditions for growth aren't favorable. 
Question: What will decay is the conditions for growth aren't favorable?
answer:
roots.


question:
Fact: predicting weather requires meteorology. 
Question: What requires meteorology?
answer:
predicting weather.


question:
Fact: Proteins are an essential nutrient for animals. 
Question: _ are an essential nutrient for animals.?
answer:

Proteins.