Electromagnetic Waves question for JEE Main (JEE Main 2022 (25 Jun, Shift 1)), with solution

Answer: (B) Optical fibre

$100\ \text{THz}$ corresponds to $\lambda = \dfrac{3\times10^8}{10^{14}} = 3\ \mu\text{m}$, in the infrared (optical) region. Such signals are carried most efficiently by optical fibres.

Solution by Sreeraj P, M.Sc Physics