Catalytic converters in vehicles are effective in removing which of the following pollutants?

Catalytic converters are devices installed in the exhaust systems of vehicles to reduce harmful emissions. They are particularly effective at converting nitrogen oxides (NOx) and carbon monoxide (CO) into less harmful substances.

When it comes to nitrogen oxides, catalytic converters facilitate a chemical reaction that transforms these reactive compounds into nitrogen and oxygen—elements that make up the majority of our atmosphere and are non-toxic. Similarly, carbon monoxide, a poisonous gas produced from incomplete combustion, is converted into carbon dioxide through an oxidation reaction within the catalytic converter.

Other options mention pollutants that do not involve the typical reactions that catalytic converters are designed to perform. For instance, sulfur dioxide (SO2) is typically minimized by different technologies, while ammonia (NH3) and methane (CH4) are not the primary targets for catalytic converters in standard automotive applications. Carbon dioxide (CO2) is a product of combustion and is not converted by catalytic converters, while particulate matter requires different filtration systems, such as diesel particulate filters, to be effectively managed. Thus, the capacity of catalytic converters to address NOx and CO emissions solidifies the correctness of the answer.