A metal conducts heat in a similar way to electricity so, as you touch it, it draws heat from your body and makes your hand feel cold. Plastics don't have to conduct heat so they don't draw heat from your body as efficiently; that's why a piece of plastic
feels than a piece of metal even if it's at the same temperature.
A) long-chain molecules; warmer
valence electrons; colder
B) free electrons, warmer
D) a crystalline lattice; colder