If you were asked to describe metals and magnetism you could say

A. non–paired electrons spin in opposite directions in all metals, creating a magnetic field.

B. metals are magnets because they have more electrons than non–magnetic materials.

C. metals can become magnetic if they have many spinning electrons that create magnetic fields.

D. the electrons in some metals pair up to create a magnetic field.

Question

If you were asked to describe metals and magnetism you could say

A. non–paired electrons spin in opposite directions in all metals, creating a magnetic field.

B. metals are magnets because they have more electrons than non–magnetic materials.

C. metals can become magnetic if they have many spinning electrons that create magnetic fields.

D. the electrons in some metals pair up to create a magnetic field.

mathslover · Answer

D) The electrons in some metals pair up to create a magnetic field.

Some metals having unpaired electrons contain a strong magnetic response i.e. they can be magnetised by an external magnetic field , they are referred to as $\textbf{ferromagnets}$ .

kfujioka · Answer

Interesting.  I would've gone with C.  Although I'm not entirely happy with the wording of it.  I understand magnetism in metals as a cooperative effect from the alignment of electron spins.  For (D), when I think of electrons pairing, that makes me think of Cooper pairs and superconductivity.