What is the primary function of catalytic converters in vehicles?

The primary function of catalytic converters in vehicles is to convert harmful gases produced during combustion into less harmful gases. The catalytic converter contains catalysts, typically made of platinum, palladium, and rhodium, that facilitate chemical reactions without being consumed in the process.

During the combustion of fuel in an engine, harmful gases such as carbon monoxide (a toxic gas), unburnt hydrocarbons (which contribute to smog), and nitrogen oxides (which can lead to acid rain and respiratory problems) are formed. The catalytic converter transforms these gases into safer emissions: carbon dioxide and nitrogen (which constitutes a large part of the air we breathe), and water vapor. By maximizing the efficiency of these conversions, catalytic converters play a critical role in reducing the environmental impact of vehicle emissions and meeting regulatory standards for air quality.

The other options, while they may relate to vehicle performance in some way, do not accurately describe the specific function of the catalytic converter. Enhancements to engine power or fuel efficiency are typically achieved through other engineering solutions, and reducing engine noise relates more to sound-proofing or exhaust design rather than gas transformation.