Extraction depends on metal's reactivity position

Steps:

• Position X between Fe and Cu in series: less reactive than Fe, more than Cu.
• Method 1 (electrolysis of oxide): used for highly reactive metals above Al; X too low.
• Method 2 (heating oxide with carbon): works for metals below Al, like Fe and X, as carbon more reactive.
• Method 3 (heating oxide with Cu): displacement requires more reactive metal; Cu below X, so ineffective.

Why C is correct:

• Carbon reduces oxides of metals less reactive than carbon (below Fe in series), extracting X efficiently.

Why the others are wrong:

• A: Includes electrolysis (1) and Cu displacement (3), both unsuitable for X's moderate reactivity.
• B: Includes electrolysis (1), reserved for very reactive metals like Al.
• D: Includes Cu displacement (3), impossible as Cu less reactive than X.

Final answer: C