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.

Input: Consider Input: Fact: Producers use unsaturated fatty acids to store energy. 
Question: What kind of organism uses unsaturated fatty acids to store energy?

Output: producers.


Input: Consider Input: Fact: A person's elbow straightens when muscles antagonistic to biceps contract. 
Question: A person's elbow straightens when muscles antagonistic to what contract?

Output: biceps.


Input: Consider Input: Fact: A porcupine will extend its spines when threatened. 
Question: What does a porcupine do with its spines when it's threatened?


Output: Extend them.