Q.Fiber optic communication is gaining popularity among the various transmission media -- justify.

Step 1. What fibre-optic communication is. It transmits information as pulses of light through an optical fibre, using total internal reflection, at very high light frequencies (400-790 THz) compared to microwave radio. Fibres are made of silica glass (abundant) or, in specialised cases, chalcogenide glasses/fluoroaluminate crystalline materials for better infrared transmission.

Step 2. Merits that justify its popularity. (i) Fibre cables are very thin and weigh far less than copper cables of comparable capacity.

(ii) The system has a much larger bandwidth, meaning a much larger information-carrying capacity than copper.

(iii) Being non-conductive, fibre optic systems are immune to electrical and electromagnetic interference, which also makes them preferred wherever multiple channels must be laid together.

(iv) Fibre optic cables are cheaper than copper cables of equivalent capability.

Step 3. Demerits, weighed against the merits. Fibre cables are more fragile than copper wires, and the technology is comparatively expensive to deploy -- but these costs are outweighed by the bandwidth, weight and interference-immunity gains for most modern high-capacity applications. …

List the fibre-optic merits and demerits from the text, then justify popularity by weighing merits against demerits and citing real- …

• Listing only merits and ignoring the demerits the question implicitly expects to be weighed against ('justify'). …