The correct option is C Molten CaH2
The fused CaH2 on electrolysis produces H2 gas on anode instead of cathode because CaH2 yields H− ion on fusion and as it is anion gets discharged at anode that is positive electrode.
CaH2⟶Ca++2H−
At anode : 2H−⟶H2+2e
At cathode : Ca++2e⟶Ca
CaH2 is an ionic hydride, which conducts electricity in the molten state.