Correct option is C
Ferromagnetic materials are those that can be magnetized and exhibit strong magnetic properties. The most common ferromagnetic materials are iron, cobalt, and nickel. These materials have unpaired electrons and their magnetic moments tend to align parallel to each other, resulting in a strong overall magnetic field. Nickel, in particular, is well-known for its ferromagnetic properties and is used in various magnetic applications. The other materials listed, such as tungsten, aluminium, and copper, are not ferromagnetic and do not exhibit strong magnetic properties in their pure form.
