How is an electromagnet different from a bar magnet?

A) Bar magnets have a north and south pole, but electromagnets do not.

B) Electromagnets are strong, permanent magnets, but bar magnets are always weaker.

C) Electromagnets are only magnetized when a current flows through a wire wrapped around the core.

Eliminate

D) Bar magnets are attracted to ferromagnetic substances such as iron. Electromagnets are attracted to all metals.