B) A stone floor feels very cold to bare feet in winter, but a carpet in the same room feels comfortably warm. Why is this?

A stone floor feels very cold to bare feet in winter, but a carpet in the same room feels comfortably warm.This is because both the floor and the carpet have the same temperature as both are exposed to the same atmosphere. But the former conducts away the heat from the feet better than the carpet as the latter is a non-conductor. So the feet losing more heat, the floor appears cooler to the feet

Explanation:

Hope it may help you!!

Both actually have same temperature. Our feet are warm. Floor is conductor of heat while carpet is not. When we walk on floor, then floor takes away or conducts the heat from our feet, so we feel cold. While carpet doesn't do that, so we feel warm.