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

[EX Q]: Most intestinal worms take _ to four weeks for maturation from their larval stages into adults.
[EX A]: three

[EX Q]: Psychoanalysis is an intensive form of psychotherapy that meets _ to five times a week.
[EX A]: four

[EX Q]: Fuel cells operate quietly and are _ to low emissions, comparable to a battery-powered vehicle.
[EX A]:
zero