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

Q: Sociobiology is the historical outgrowth of _ prerequisite trends.

A: three
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Q: Silks are susceptible to infection during the first _ days after initiation.

A: five
****
Q: Incubation takes about four weeks, and the owlets fledge after about _ month.

A:
one
****