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

Example Input: Arthritis is the leading cause of disability in the state affecting about one in _ adults.
Example Output: three

Example Input: Cleavage is imperfect in _ directions, prismatically.
Example Output: two

Example Input: Pathogens can enter our bodies through _ routes.
Example Output:
four