Answer;
C. a permanent magnet.
A ferromagnetic material that has domains that remain aligned for a long period of time is called a permanent magnet.
Explanation;
- Permanent magnets are either ferromagnetic or ferrimagnetic materials.
- Ferromagnetic materials such as iron, nickel and steel have a large, positive susceptibility to magnetic fields. These materials are strongly attracted to magnetic fields and are capable of retaining their magnetic properties after the removal of the external field.
- Ferromagnetic materials attain strong magnetic properties since they have magnetic domains.
- When these materials are fully magnetized the domains are aligned to produce strong magnetic field resulting to formation of permanent magnets.
