In this task, you are given a question and an answer, you would be asked to create the sentence based on the Question-Answer provided. It should be contained within the Question-Answer provided.

[EX Q]: Question: If a substance does not release molecules into the air from its surface, it will not have what? Answer: smell
[EX A]: If a substance does not release molecules into the air from its surface, it will not have a smell.

[EX Q]: Question: What forms a ketone when oxidized? Answer: secondary alcohol
[EX A]: Secondary alcohol forms a ketone when oxidized.

[EX Q]: Question: In the freshwater flatworms, protonephridia serve chiefly in what? Answer: osmoregulation
[EX A]:
In the freshwater flatworms, protonephridia serve chiefly in osmoregulation.