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.

[Q]: Question: The body contains how many types of muscle tissue? Answer: three
[A]: The body contains three types of muscle tissue.


[Q]: Question: All solutions contain at least how many substances? Answer: two
[A]: All solutions contain at least two substances.


[Q]: Question: What is critical for the formation of hemoglobin? Answer: iron ions
[A]:
Iron ions are critical for the formation of hemoglobin.