What is the maximum time allowed to undo the sending of an email using the Undo Send lab?

The maximum time allowed to undo the sending of an email using the Undo Send feature in Gmail is indeed set at 30 seconds. This feature provides a brief window during which you can retract an email after hitting the send button, giving you a chance to correct any mistakes or reconsider the send action. The 30-second timeframe is carefully chosen to balance between providing adequate reflection time while maintaining the efficiency of email communication. This allows users to quickly reverse their decision on sending the email without introducing excessive delays.

Other options propose times that are shorter or longer than 30 seconds, which do not align with the functionality as specified in Gmail's settings. The feature is designed to support user decision-making promptly without extending the cancellation period unnecessarily.