The word that is closest in meaning to "correspondence" is letters.

• Argument means a discussion or disagreement in which people express different opinions about something.
• Contracts are legal documents that establish an agreement between two or more parties.
• Address is a person's home or business location.

"Correspondence" means the exchange of letters or other written messages between people. It can also refer to the letters or messages themselves. "Letters" is the most accurate synonym for "correspondence" in this context, as it means a written message sent from one person to another.