Final answer:
Fiber optic transmission occurs in the infrared part of the spectrum, utilizing the principle of total internal reflection to transfer light over long distances with high bandwidth.
Step-by-step explanation:
Fiber optic transmission takes place in the infrared portion of the spectrum. This type of transmission employs light that is guided down fibers of plastic or glass based on the principle of total internal reflection. Because of the high transparency and the low-loss properties of the optical fibers, light can travel over long distances and with higher bandwidth compared to copper conductors. As a result, optic transmission is widely used in telecommunications such as carrying telephone and internet communications, with extensive fiber optic cables laid on ocean floors and underground.