Answer:
The correct option is;
d. A coil
Step-by-step explanation:
When a wire, which is an electric conductor is formed into the shape of a coil, and current is allowed to flow through the wire coil, a magnetic field is generated
The magnetic field generated by the electromagnetic coil has direction that consists of flux emanating from one end of the coil and entering the coil from the other end, similar to that of the magnetic field produced by a normal bar magnet.