What is required for a vehicle's fuel system to pass inspection?

For a vehicle's fuel system to pass inspection, it must demonstrate that there are no leaks and that it is functioning properly. This requirement is critical because any leaks can lead to significant safety hazards, including fire risks and environmental concerns. A properly functioning fuel system ensures that the engine receives the correct amount of fuel, contributing to safe operational performance and optimal emissions control.

The other options focus on aspects that are not necessary for passing a safety inspection. For instance, modern fuel type and brand are not standard requirements; vehicles may have different fuel system specifications regardless of their fuel types. Fuel efficiency ratio and average fuel consumption are also performance metrics that, while useful for assessing vehicle efficiency, do not impact the safety and compliance aspects of the inspection. Thus, the emphasis is clearly placed on the integrity and performance of the fuel system itself to ensure it is safe for operation.