Catalytic converters, which are fitted into automobiles for reducing emission of poisonous gases, use which of the following expensive metals as catalysts?

Correct answer: Platinum-palladium and Rhodium

Catalytic converters use platinum-palladium and rhodium as catalysts to facilitate chemical reactions. These metals help convert unburnt hydrocarbons into CO2 and water, and carbon monoxide and nitric oxide into CO2 and nitrogen gas.