Which telephone feature allows an incoming call to roll to the next number when faced with a busy line?

The feature that enables an incoming call to roll to the next number when faced with a busy line is known as rollover. This is particularly useful in a business context where multiple lines may be in use; rollover ensures that calls can still be received without having to wait for one of the lines to become available. Instead of hearing a busy signal, the caller is automatically directed to the next line in the sequence.

This feature enhances communication efficiency by minimizing lost calls and ensuring that customers can reach someone even during peak times. In contrast, call waiting allows a person already on a call to be notified of an incoming call without dropping the ongoing call, while voicemail provides a means for callers to leave messages when the recipient is unavailable. Call forwarding directs calls to another number entirely, rather than rolling them over to another line when busy. Rollover specifically addresses busy lines, making it the most appropriate choice.