Exam 10: Object-Oriented Programming: Inheritance

Which of the following pairs demonstrates the "has-a" relationship?

The default implementation of method ToString of Object returns a String representing ________.

To call the base-class default constructor explicitly,the call to a base-class constructor must be the first statement in the derived-class-constructor definition.

A class that implements an interface may not act as a base class for other classes.

A base class may have only one derived class.

The MustOverride keyword has the same effect as the Overridable keyword.

Abstract classes are classes which may not be:

The class hierarchy begins with class __________.

All objects of a class are guaranteed to provide the functionality described by any interface that the class implements.

The use of polymorphism helps promote software extensibility.

__________ is a form of xe "code reuse"xe "software reuse"software reuse in which a new class is created quickly and easily by absorbing an existing class's members and customizing them with new or modified capabilities.

Polymorphism enables you to conveniently xe "program in the general"program "in the general" rather than "xe "program in the specific"in the specific."

Which of the following properties could exist in an interface for files,cats and houses?

Polymorphism involves:

Classes which may be instantiated are ___________ classes.

Which of the following pairs demonstrates the "is-a" relationship?

You may define implementations for abstract methods to act as a default.

Which of the following could be a base class for class Computer?

Assigning a derived class reference to a base class variable is safe:

Every class in Visual Basic except __________ extends an existing class.