Which is a combining form, not a prefix or a suffix? a. centesis b. patho c. opsy d. retro

The correct answer is B. Patho is a combining form, not a prefix or a suffix, as it is a word that has a meaning by its own.

Explanation:

Pathos is one of the two forces that regulate the human soul according to Greek thought. It opposes the Logos, which is the rational part. Pathos in fact corresponds to the irrational part of the soul. It can have both positive and negative connotations depending on the context.  

For the ancient Greeks this "emotional force" was closely connected to the Dionysian realities or in any case of the mystery rites. For this reason Pathos indicated all the irrational instincts that bind man to his animal nature and prevent him from rising to the divine level.