Final answer:
For thermal curling combs, wood or ceramic materials are suitable because they can withstand high temperatures without conducting excessive heat or melting, unlike metal or plastic.
Step-by-step explanation:
Combs used for thermal curling should be made of materials that can withstand high temperatures without melting or conducting too much heat that could lead to burns. The correct material for thermal curling combs is wood or ceramic. Metal and plastic are not suitable materials for this use because metal is a good conductor of heat, potentially leading to burns, and plastic could melt when exposed to high temperatures used for curling hair.
Two materials that are good thermal conductors are metals such as copper and aluminum. On the other hand, two materials that are good insulators would include wood and plastic. These insulators are used in contexts where it is essential to minimize the transfer of heat.