Depot plates may be used during normal business hours to transport a motor vehicle that is?

Depot plates are specialized plates issued to vehicle dealerships for use on vehicles that are not registered to individual owners but are part of the dealership's inventory. When it comes to transporting motor vehicles with depot plates, they can be utilized during normal business hours for a range of purposes.

All of the listed conditions—properly registering a vehicle, assigning it in the name of the dealership, and making it available for sale—are aligned with the purpose of depot plates.

A vehicle that is properly registered enables the dealership to be compliant with legal requirements when it comes to operation and transport. Assigning a vehicle in the name of the dealership signifies that the vehicle is indeed part of the dealership’s inventory and ownership. Furthermore, having a vehicle available for sale means it is part of the dealership's business operations, directly linking to why depot plates are permissible during regular business hours.

Thus, the ability to use depot plates for all these conditions reflects the versatility and functionality intended for them within dealership operations, affirming that the answer covers all these scenarios.