Avariable declared to be of one class can later reference an extended class of that class. this variable is known
a. public
b. derivable
c. cloneable
d. polymorphic
e. none of the above, a variable declared to be of one class can never reference any other type of class, even an extended class

Option (D) i.e., polymorphic is the correct answer to the following.

Explanation:

Because polymorphism is the concept of the Object-Oriented Programming in which an object or method having same in name.

Polymorphism is one of the essential features of the OOPs in which the method having the same name but different in their argument or the parameter list, in other words, the items having the same names but different in their working.

the answer is d underlined.

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