Which one of the following is an insulator for electricity but a conductor for heat?

مندرجہ ذیل میں سے کون سا بجلی کے لئے انسولیٹر ہے لیکن گرمی کے لئے ایک موصل؟

Iron

Diamond

Graphite

None of these

Diamond is an excellent conductor of heat due to strong covalent bonding and crystal structure.

It is a strong electrical insulator because it lacks free electrons to carry current.