How to create a class that “extends” two existing concrete classes

Question

I very well know that it can be done with the help of interfaces and i have done it many times. But this time my situation is quite difference. I have class A ,

Answer 1

A common oop principle is "choose composition over inheritance", since you can't extend 2 classes I would suggest having one of or both of those classes as members of Class C, that is of course if that works for what you are trying to do.