Question

sort the words according to the meanings of their shared roots. octopod tripod intermediate cryptic podiatrist encryption medium decryption middle hide foot

Explanation:

The root "medi -" means middle, so "intermediate" and "medium" go in the "middle" category. The root "crypt -" means hide, so "cryptic", "encryption", and "decryption" go in the "hide" category. The root "pod -" means foot, so "octopod", "tripod", and "podiatrist" go in the "foot" category.

Answer:

middle: intermediate, medium
hide: cryptic, encryption, decryption
foot: octopod, tripod, podiatrist