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.

Example Input: Question: Carbon dioxide does not rise like other gases because it has a density greater than what? Answer: air
Example Output: Carbon dioxide does not rise like other gases because it has a density greater than air.

Example Input: Question: Which of the following structures is not present in animal cells? Answer: cell wall
Example Output: A cell wall is not present in animal cells.

Example Input: Question: Compounds containing which element are the basis of all known life? Answer: carbon
Example Output:
Compounds containing the element carbon are the basis of all known life.