What is required for a vehicle to be considered a bus?

For a vehicle to be classified as a bus, it must have a capacity of over 10 persons, including the driver. This definition is based on established regulations that distinguish different types of vehicles based on passenger capacity. A bus is typically intended for transporting a larger number of passengers and is designed to accommodate more than just a small group, which aligns with the requirement of having seating for more than 10 individuals.

The other options do not define a bus in the context of regulations. While painting buses yellow is commonly associated with school buses in certain regions, it is not a universal requirement for all buses. Operating a fixed route can apply to many types of public transport, but it does not determine whether a vehicle's classification as a bus. Similarly, wheelchair access is an important feature for accessibility but is not a defining characteristic of what constitutes a bus. Therefore, the correct criterion focuses solely on the number of passengers the vehicle can carry.