D vs C++ classes?

[Ola Fosheim Grøstad]

On Tuesday, 22 June 2021 at 15:14:02 UTC, mw wrote:
> Class D : B(disable a), C ｛｝ // so using C.a()
>
> Class D : B, C(disable a) ｛｝ // so using B.a()

I don't really see the difference between this and forcing a 
reimplementation of `a()` that calls A's `a()`, B's `a()` or both.