CompTIA Network+ Question C-9

A T1 line has lost connectivity to the ISP. The ISP has instructed the technician to place a loopback on a device connecting the T1 line to their central office. On which of the following devices will the technician implement the loopback?

A. Channel remote module
B. Fiber optic modem
C. Channel service unit
D. Digital subscriber line modem

Correct Answer: C