Which of the following actions is appropriate for sending a notification in Pega?

The most appropriate action for sending a notification in Pega is to add a Send Correspondence step to the assignment. This option directly relates to the functionality in Pega for managing communication with users, which includes sending notifications via email or other correspondence methods. The 'Send Correspondence' step is specifically designed to facilitate the sending of messages and notifications as part of the workflow process.

This step allows users to define the recipients, content, and type of communication needed, ensuring that users can effectively notify stakeholders or users of important updates or information. This capability streamlines communication within the application and ensures that notifications are sent at the correct time within the workflow.

In contrast, adding a notification to a connector or a decision shape for email handling does not directly provide the structured process for notifications that the 'Send Correspondence' step offers. Similarly, while adding a standard activity to the workflow might allow for various actions, it does not specialize in the targeted sending of notifications like the correspondence step does.