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

Example Input: Ticks mature in _ stages, moving from egg to larva and nymph to adult.
Example Output: four

Example Input: Giraffes have two horns and _ or three knobs.
Example Output: two

Example Input: Most spiders have _ eyes, but some, like the brown recluse spider, only have six.
Example Output:
eight