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: One-celled animals can be partially classified on the basis of how they move. 
Question: Movement is one classification method for what?
answer:
one-celled animals.


question:
Fact: The volume of an object can be used to measure the mass of the object. 
Question: The volume of an object can be used to measure what?
answer:
the mass of the object.


question:
Fact: a warm front causes storms. 
Question: What does a warm front cause?
answer:

storms.