Both the Code and the Restatement provide that an authorized means of accepting an offer is any reasonable means of communication.

Code

A system of principles or rules.

Restatement

The act of rephrasing or reiterating something, often for clarity, or in law, a document that systematically presents legal rules and principles.

Reasonable Means

Methods or actions that are considered sensible and appropriate under the circumstances, often used in the context of achieving a specific legal or procedural outcome.