At times we all regret decisions. Does this necessarily mean we did not use the economic decision rule when making the decision?

A. Message element of the communication model

Explanation:

The communication model basically consists of four factors namely; the sender, the message, the receiver, and the channel. The sender in this context is Tony. Since he is nervous about delivering the information that he has, his concerns relate to the message element in the communication model.

The information is the message Tony wants to pass. So his nervousness is about delivering the message well.