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: All cells undergo what during a lifetime, but when this process is out of control, cancer results? Answer: cell division
[EX A]: All cells undergo cell division during a lifetime, but when this process is out of control, cancer results.

[EX Q]: Question: Trees release what gas as a byproduct of photosynthesis, thereby facilitating human respiration? Answer: oxygen
[EX A]: Trees release oxygen gas as a byproduct of photosynthesis, thereby facilitating human respiration.

[EX Q]: Question: What is the ph of pure water? Answer: 7
[EX A]:
7 is the ph of pure water.