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

Input: Consider Input: Rams can be policerate, often producing _ horns.

Output: four

Input: Consider Input: Mice are fertile animals because female mice come into heat every _ to five days.

Output: four

Input: Consider Input: Induction also operates early in development, even before the _ layered embryo forms.
Output: three