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.

[Q]: Fact: measuring diamonds requires scratching them. 
Question: What can you scratch to measure?
[A]: diamonds.


[Q]: Fact: the stomach acidity helps digest fats. 
Question: What helps digest fats?
[A]: stomach acidity.


[Q]: Fact: running requires a lot of calories. 
Question: What does the body use while running?
[A]:
Calories.