If a thermal conductor is exposed to a source of heat then that conductor may become hot.
Copper is a great thermal conductor.
If copper is exposed to a source of heat then it may become hot.
What material will become hot if exposed to a heat source?
1: coal
2: asbestos
3: polystyrene
4: Oak
5: Fiberglass
6: Copper
7: bamboo
8: an object