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.

Example Input: Fact: Aging is associated with apoptosis. 
Question: What stage is associated with apoptosis?
Example Output: aging.

Example Input: Fact: Plant growth in width or girth emanates from within and around the vascular tissues. 
Question: Where in the plant does growth in width or girth originate?
Example Output: vascular tissue.

Example Input: Fact: Unequal heating of Earth 's surface by the Sun causes polar easterlies. 
Question: Unequal heating of Earth 's surface by what causes polar easterlies?
Example Output:
sun.