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

Example Input: Pollination is accomplished only by insect-agency, and where insects fail _ fruits are ripened.
Example Output: no

Example Input: All dogs are animals, and no cats are dogs, therefore _ cats are animals.
Example Output: no

Example Input: All Dishevelled proteins have _ highly conserved domains.
Example Output:
three