In this task, find the most appropriate number to replace the blank (indicated with _ ) and express it in words.

[EX Q]: Presta valves are the skinnier of the _ valve types.
[EX A]: two

[EX Q]: Slime molds have _ life cycle stages.
[EX A]: two

[EX Q]: Today there are _ main areas of focus in applied sports psychology.
[EX A]:
three