Which one of the following could be a paramagnetic substance?

Correct option is B

Correct answer is B
Explanation:
Paramagnetic substances are materials that exhibit magnetism only in the presence of an external magnetic field. This property arises due to the presence of unpaired electrons in the material.
· Lead: Lead is diamagnetic and does not exhibit paramagnetism.
· Gadolinium: Gadolinium is paramagnetic due to unpaired electrons in its atomic structure.
· Silicon: Silicon is diamagnetic and does not exhibit paramagnetism.
· Oxygen: Oxygen in its gaseous state (O2 ) is paramagnetic due to the presence of unpaired electrons in its molecular orbitals.
Therefore, the correct answer is Option 2.