Which of the following is not a transmission medium?
choose one answer.
a. coaxial cable
b. twisted-pair cable
c. smartphone
d. telephone line

A transmission medium is device that carries data between 2 computer sysyems. The transmission medium to your house is likely copper wire or fibre optic (for internet), your smartphone uses wifi or cellular

The answer is smartphone, a smartphone is a computer system not a transmission medium.

The correct answer would be a.

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