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

Example Input: Babies can range in age from newborn up to _ years old.
Example Output: three

Example Input: Southern moles are six to seven inches long and weigh _ to four ounces.
Example Output: three

Example Input: Babies can be exclusively breast-fed for their first _ months of life.
Example Output:
six