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.

[EX Q]: Fact: planes can measure wind speed. 
Question: what can measure wind speed?
[EX A]: planes.

[EX Q]: Fact: Pollen grains are small male reproductive bodies of plants used to pollinate female flowers. 
Question: pollen grains are small male reproductive bodies of plants used to pollinate what?
[EX A]: female flowers.

[EX Q]: Fact: Clams have a circulatory system with one or two hearts. 
Question: have a circulatory system with one or two hearts?
[EX A]:
Clams.