Which of the following would not be permitted to operate an ambulance with passengers?

The correct answer indicates that a holder of a Class 3 operator's licence would not be permitted to operate an ambulance with passengers. This is based on the classifications of driver's licenses in Alberta, which specify the types of vehicles that can be operated depending on the license held.

A Class 3 operator’s licence is intended for driving heavy trucks and vehicles with a weight exceeding a certain limit, but does not include the authority to operate ambulances that may carry passengers. In contrast, a Class 1 operator's licence allows for the operation of all classes of vehicles including heavy vehicles with trailers, and a Class 2 operator's licence permits the operation of buses designed to carry passengers. The Class 4 operator’s licence specifically covers emergency vehicles, including ambulances, which is why holders of this license can operate ambulances with passengers.

Thus, the holder of a Class 3 operator's licence lacks the necessary authority to operate an ambulance, making it clear why this option is the correct answer.