Final answer:
Option D. To prevent scratching the painted surfaces of a car while working in the engine compartment, technicians use a fender cover, typically made of materials like foam or reinforced vinyl.
Step-by-step explanation:
While working in the engine compartment to protect the painted surfaces from being scratched by a technician's belt, a fender cover is typically used. This type of cover is designed to provide a soft protective layer over the edges of the fender, which are areas most prone to getting scratched or dinged by tools, belts, or the technician's clothing. The correct answer to the question is D) fender cover.
Fender covers come in various materials such as foam, leatherette, or reinforced vinyl, and they usually feature a non-slip backing to stay in place. These covers are not only important for protecting the vehicle's paint but also for the safety of the technicians, as they can prevent tools from slipping and causing injuries.