Extraction method depends on reactivity series position Steps: - Place X in reactivity series: more reactive than zinc (below carbon) but less than sodium (above carbon), so X is above carbon (e.g., like Mg or Al). - Metals above carbon cannot be reduced by carbon or hydrogen; require electrolysis of molten compounds. - For oxide ores of such metals, molten electrolysis avoids water decomposition issues in aqueous solutions. - Select method matching this: electrolysis of molten oxide. Why B is correct: - Electrolysis of molten oxide directly yields pure metal for highly reactive metals above carbon, as in Hall-Héroult process for Al (formula: Al2O3 → 2Al + 3/2 O2 at anode/cathode). Why the others are wrong: - A: Aqueous solutions electrolyze water first (2H2O → 2H2 + O2) for metals more reactive than hydrogen, preventing metal deposition. - C: Hydrogen reduction suits moderately reactive metals (e.g., CuO + H2 → Cu + H2O) but fails for very reactive X due to weak reducing power. - D: Carbon reduction (e.g., ZnO + C → Zn + CO) works only for metals …