Which ofthe following is not a guided medium?

1 TwistedPair

2 Fiber OpticCable

3 CoaxialCable

4Atmosphere

Answer: 4. Atmosphere.

Explanation:

All the other 3 options Twisted pair, Fiber Optic Cable, Coaxial Cable comes under guided media also known as bounded media. While Atmosphere doesn't come under this category. It is an unbounded media. The signal is not bounded in atmosphere while in other 3 options the signal is being transmitted through a wire.