On a cold day when a room temperature is 15oC, the metallic cap of a pen becomes

CuriousTab

Question
On a cold day when a room temperature is 15^oC, the metallic cap of a pen becomes much colder than its plastic body, though both are at the same temperature of 15^oC, because
Options
A. metals have higher thermal capacity than plastics
B. plastics have a lower density than metals
C. metals are good conductor of heat
D. plastics have a higher thermal conductivity than metals