Concept:Relinquish means to voluntarily give up something. Its synonym is Abandon.Explanation:Relinquish refers to letting go of a possession, right, or claim. Abandon also means to leave something completely or give it up. Both words convey the idea of surrendering or ceasing to hold. The other options are antonyms: Maintain means to keep, Continue means to persist, and Retain means to hold onto. Thus, Abandon is the correct synonym.Answer:A. Abandon