A technician has traced a POTS line to a 110 block. Which of the following devices would the technician MOST likely use to see if the line carries a dial tone?

A toner probe is used to identify and trace a specific cable run through conduit or walls and cannot interface with a POTS line to test for a dial tone.

A punch down tool is used to terminate wires into the 110 block connectors and is not capable of testing line signal or dial tone.

A protocol analyzer captures and decodes digital network traffic and has no ability to interface with or test an analog POTS telephone line.

A butt set (also called a lineman's handset or test set) clips directly onto the terminals of a 110 block or other punch-down termination and allows a technician to listen for a dial tone, make test calls, and perform basic POTS line diagnostics. It is the standard tool used by telephone technicians for analog line testing at punch-down blocks. No other common IT tool provides direct analog telephone line access in this way.