Create an abstract Vehicle class implementing an ICarbody interface

Question

An abstract Vehicle class implementing an ICarbody interface:

Accepted Answer

Classes derived from Vehicle must implement the methods of the parent class and those of the interface

Accepted Answer

Defined for example as follows: public abstract Vehicle: ICarbody {...}

Answer

Classes derived from Vehicle should only implement parent class methods

Answer

Is defined for example as follows: public ICarbody : abstract Vehicle{...}

Question from the C# - Fundamentals test