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

Input: Consider Input: Sociobiology is the historical outgrowth of _ prerequisite trends.

Output: three


Input: Consider Input: Mental illness affects _ out of four families in America.

Output: one


Input: Consider Input: Neutrality is a _ quantity that helps the stronger party in an unequal struggle.


Output: zero