What will be deposited at the cathode on the electrolysis of fused NaCl?

Sodium

The correct answer is: 3. Sodium

During the electrolysis of fused NaCl (molten or in a state of fusion), the compound dissociates into its constituent ions:

NaCl(l) → Na⁺(l) + Cl⁻(l)

At the cathode (the electrode where reduction occurs), positively charged sodium ions (Na⁺) are attracted and gain electrons to form sodium atoms (Na). These sodium atoms then combine to form elemental sodium (Na), which gets deposited at the cathode.

So, during the electrolysis of fused NaCl, sodium (Na) will be deposited at the cathode. The chloride ions (Cl⁻) are attracted to the anode (the electrode where oxidation occurs) and undergo oxidation to form chlorine gas (Cl₂).