How to Inherit method but with different return type?

Question

Given the following classes:

ClassA
{
     public ClassA DoSomethingAndReturnNewObject()
     {}    
}

ClassB : ClassA
{}

ClassC : ClassA
{}

Answer 1

I think that you need to create a new function with the new return type and call inside the other function, and manipulate the type returned. otherwise it will no be logical ! (with the definition/idea of inheritance)