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

[EX Q]: Miniature cattle are classified in _ categories as measured by height at the hip.
[EX A]: three

[EX Q]: Aquatic adults have prominent red reathery gills, are large, and have _ toes on each foot.
[EX A]: four

[EX Q]: Nymphs are baby lice that mature in about _ days.
[EX A]:
seven