Which of the Following Would Correctly Call the Base Class

Multiple Choice

Which of the following would correctly call the base class BaseClass) assignment operator from the derived class DerivedClass) assignment operator?
DerivedClass& DerivedClass::operator =const DerivedClass& rightSide)
{
//what goes here?
}

A) BaseClass::operator=rightSide) ;
B) leftSide=rightSide;
C) rightSide=BaseClass.rightSide;
D) DerivedClass::rightSide=BaseClass::rightSide;