In this task, you are given a sentence and a question, you would be asked to create the answer which is contained in the sentence provided.

[Q]: Sentence: In weather terms, the boundary between two air masses is called front. Question: In weather terms, what do you call the boundary between two air masses?
[A]: front


[Q]: Sentence: The distinctive appearance of cartilage tissue is due to polysaccharides called chondroitin sulfates. Question: The distinctive appearance of what tissue is due to polysaccharides called chondroitin sulfates?
[A]: cartilage


[Q]: Sentence: Allele frequecy is the rate at which a specific allele appears within a population. Question: What is the rate at which a specific allele appears within a population called?
[A]:
allele frequecy