What feature allows users to save frequently used email responses in Gmail?

The correct answer is Canned Responses. This feature in Gmail enables users to save and reuse frequently used email replies, enhancing efficiency and productivity in email communication. By creating a Canned Response, you can store a complete email template that can be quickly inserted into a new message when needed.

This is particularly useful for common inquiries or standard replies that you find yourself sending on a regular basis, allowing you to respond faster without having to type out the same message repeatedly. Users can access their saved responses through the compose window, making it simple to incorporate them into conversations.

Other features, while useful in their own right, do not serve the same purpose as Canned Responses. Email Forwarding is designed for sending an email to another address, Email Threads organize email conversations for easier navigation, and Labeling helps categorize and manage emails but does not facilitate the reuse of message content.