A class 3 vehicle that exceeds 2.05 metres in width must have:

Answer: C — Identification and clearing lights

A class 3 vehicle is typically a large commercial vehicle such as a truck or bus. Since it exceeds 2.05 metres in width, it requires additional safety measures to ensure visibility on the road. Option A and B are incorrect because signal lights and brake lights are standard for all vehicles, regardless of size. Fog lights (option D) are not required for all vehicles and are only meant to improve visibility during inclement weather conditions. Therefore, option C is the correct answer as identification and clearing lights are specifically for wide vehicles to alert other drivers of its size and provide clearance lights for visibility.