Suppose this is embedded in an otherwise correct and complete program. Which version of f() will be called?

Suppose class D is derived from class B, and class B has a public member function whose declaration is virtual void f();. Suppose class D has its version of the function, void f(). Here is a function definition and an invocation.
```
void g( B& b)
{
// other code
b.f();
// other code
};

g( dObject );
```

a) D::f()
b) B::f()
c) This is illegal. You can’t pass a D object argument for a B reference
parameter.

a) D::f()