Why is twisted pair wire desirable for telephone use?

Twisted pair wire is particularly desirable for telephone use primarily because it is less likely to pick up electrical interference. The design of twisted pair cables consists of pairs of wires that are twisted together at specific intervals. This twisting helps to cancel out electromagnetic interference that can be induced from external sources, such as radio frequency interference (RFI) or electrical noise from nearby cables and equipment.

By minimizing the effects of such interference, twisted pair wires ensure that voice signals transmitted over telephone lines maintain clarity and quality, reducing the likelihood of distortion or loss of signal quality. This characteristic makes twisted pair an optimal choice for communication systems, where clear transmission of voice data is crucial.

In evaluating the other options, while twisted pair wiring might have advantages regarding cost and installation in some contexts, those factors are secondary to its ability to maintain signal integrity in the presence of interference. Conductivity relates more to the material used in the wires—such as copper—rather than the twisting itself, which is focused on shielding and noise reduction.