Welcome to Europe
This is indeed a class B car. I had it quite a number of times when I was supposedly "upgraded". Depending on my needs, sometimes I do complain about it especially when I need the car for 4 pax, making the 2 door come rather inconvenient.
I was told by an agent once that the class are not based on the size of the car, rather on the engine size. For example, a Class A would be a 1000cc engine car and the Class B would be 1200-1300 cc engine.
Cheers!