Assertion : Fused NaH consists of Na⁺ ions and H⁻ ions
Reason : Elecrtrolysis of fused NaH liberates H₂ at anode
 

Sodium hydride is an electrovalent compound in which hydrogen is present as an anion, H⁻ (hydride ion) which is discharged as H_2​ at anode on electrolysis.

Oxidation at anode: $2{\mathrm{H}}^{-}\to {\mathrm{H}}_2\left(\mathrm{g}\right)+2{\mathrm{e}}^{-}.$

Reduction at cathode: $2{\mathrm{Na}}^{+}+2{\mathrm{e}}^{-}\to 2\mathrm{Na}.$