Which license allows you to drive a special vehicle with a gross weight of 3.5 tons or less built to perform special work (excluding wreckers, etc.)?

Answer: ③ Class 2 Ordinary license

Special vehicles with a gross weight of 3.5 tons or less (other than wreckers, etc.) can be driven with a Class 2 Ordinary license. Learner's licenses are only for practice in ordinary vehicles, and the Class 1 Small license covers three-wheeled vehicles and motorcycles. [Road Traffic Act Enforcement Rule, Annex 18]