What is the primary focus of the Federal Motor Carrier Safety Administration?

Answer: B — Safety regulations for highway vehicles

The Federal Motor Carrier Safety Administration (FMCSA) primarily focuses on ensuring the safety of commercial motor vehicles and the drivers operating them. Its core mission is to reduce crashes, injuries, and fatalities involving large trucks and buses. This is accomplished through the establishment and enforcement of safety regulations pertaining to vehicle maintenance, driver qualifications, and operational practices. Safety regulations under FMCSA cover a wide range of areas, including hours of service for drivers, vehicle inspections, and the proper handling of hazardous materials. By focusing on these safety standards, the FMCSA aims to create a safer driving environment on America's highways, thus protecting not only truck drivers but also other road users. Therefore, the focus on safety regulations for highway vehicles accurately captures the essential mission of the FMCSA.