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: Passenger pigeons could not produce enough offspring. 
Question: What could not produce enough offspring?
Example Output: passenger pigeons.

Example Input: Fact: Smog is an airborne pollutant. 
Question: What is an airborne pollutant?
Example Output: Smog.

Example Input: Fact: gases from burning coal and oil dissolving in water in the atmosphere kills trees. 
Question: what does gases from burning coal and oil dissolving in water in the atmosphere do?
Example Output:
kills trees.