The words disclosure and concealment are

A. homonyms.

B. synonyms.

C. antonyms.

D. equivalents.

The words disclosure and concealment are C. antonyms. Antonyms are words that have the opposite meanings, and given that disclosure is when you show something, and concealment is when you hide something, it is obvious that these two words are quite contrary. Homonyms are words that sound the same, but are not spelled the same. Synonyms or equivalents have the same meaning,