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

[EX Q]: Crustaceans have _ major body parts .
[EX A]: three

[EX Q]: Most children recover from croup in _ to five days.
[EX A]: three

[EX Q]: Eagles usually start to breed at four to _ years of age.
[EX A]:
nine