To renew a commercial driving licence, the transport authority requires specific documentation. A primary document is a current Fitness Certificate. This certificate verifies that the commercial vehicle is safe and compliant with all operational and safety regulations for road use. Operation of a vehicle for commercial purposes is prohibited without a valid fitness certificate. An authorized inspection center or the transport authority issues the fitness certificate following a comprehensive vehicle inspection. Although other documents such as the registration card and insurance are also mandatory, the fitness certificate uniquely attests to the vehicle's condition. Consequently, the correct response is Fitness Certificate.