In winter, two thin shirts give us more comfort than one thick shirt because

Wearing two thin shirts in winter is more comfortable than wearing one thick shirt due to the insulating effect of the air layer trapped between the two shirts. Air is a poor conductor of heat, which makes it an excellent insulator. When you wear two thin shirts, the layer of air between them acts as an insulating barrier that reduces the transfer of heat from your body to the colder external environment.

This trapped air layer minimizes heat loss and retains body warmth more effectively than a single thick shirt, which lacks this additional insulating layer. The combined effect of the two shirts and the insulating air layer creates a more efficient thermal barrier, enhancing warmth and comfort in cold weather. Thus, the correct answer is [C] The layer of air between two shirts works as a medium of insulation.