ANS:D - all (a), (b) & (c).

The statement "Electrometallurgical methods of metal extraction is normally used for those metals" - "all (a), (b) & (c)" is correct. Here's why: a. "whose oxide/ore is not reduced by carbon" - Electrometallurgical methods are indeed employed for metals whose oxides or ores cannot be reduced by carbon, such as aluminum and magnesium. b. "which fall in the category of alkali & alkaline earth metals" - Electrometallurgical methods are commonly used for extracting metals that belong to the alkali and alkaline earth metals, such as sodium, potassium, calcium, and magnesium. c. "which stands higher in the electrochemical series of the metal" - Electrometallurgical methods are typically suitable for metals that are higher in the electrochemical series, indicating their higher reactivity. These metals tend to have a stronger affinity for electrons and are more readily reduced electrochemically. Therefore, all three conditions listed in options (a), (b), and (c) are generally true for metals that are extracted using electrometallurgical methods.