Calcium carbide and aluminium nitride
Calcium phosphide and calcium cyanamide
Calcium hydride and Calcium carbide
Magnesium nitride and calcium nitride
Ca3N2 + 6H2O → 3Ca(OH)2 + 2NH3
Mg3N2 + 6H2O → 3Mg(OH)2 + 2NH3
NH3 gas released in above two reactions give NH4Cl white fumes when reacted with HCl
HCl + NH3 → NH4Cl
Hence, option C is correct.