Which of the following is used to test for continuity in a copper cable? (Choose all that apply)

A.
A multimeter

B.
A wire crimper

C.
An optical tester

D.
Time-Domain Reflectometer

Explanation:
A multimeter is a device that is used to measure voltages and resistances in electronic
components. It can also be used to test for continuity in a wire. A continuity test will indicate if
there is a break in the wire. A Time-Domain Reflectometer (TDR), which is also called a cable
tester, is a device that sends out a signal and measures the time it takes for the signal to reurn. A
break in the cable will cause the signal to return prematurely and will indicate the presence of, and
the distance to, a break in the cable.

Incorrect Answers:
B: A wire crimper is used to attach RJ-45 connectors to a cable by using pressure to press some
kind of metal teeth into the inner conductors of the cable. It is not used to test for faults in the
cable.
C: An optical tester is a device that measures the quality of strength of light signals passing
through an optical cable.Reference:David Groth and Toby Skandier, Network+ Study Guide (4th
Edition), Sybex, Alameda CA, 2005, pp. 12, 439.