In this task, find the most appropriate number to replace the blank (indicated with _ ) and express it in words.
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Question: Ticks mature in _ stages, moving from egg to larva and nymph to adult.

Answer: four

Question: Induction also operates early in development, even before the _ layered embryo forms.

Answer: three

Question: Genetic disease knows _ boundaries by age, sex, race, or country of origin.

Answer:
no