Choose the best answer from the list of options given.

Sub$-$type Polymorphism occurs when:

Select one:

a$.$ Asuperdass object is replaced by a subclass object in a reference

b$.$ A base class object calls a method that belongs to another base class

c$.$ A parent class object calls a method that belongs to a child class object

d$.$ A derived class object calls a method that belongs to another derived class

e$.$ A super class object is replaced by a super class object from another hierarchy