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: Skin color is influenced by environmental factors. 
Question: what is influenced by environmental factors?
answer:
skin color.


question:
Fact: animals use sound to find a mate. 
Question: What do animals use to find a mate?
answer:
sound.


question:
Fact: Amphibians have a chemical sensing system. 
Question: Amphibians have what sort of sensing system?
answer:

chemical.