Question 1

What is another name for a base class in C#?

Accepted Answer

A)  derived class 
B)  parent class 
C)  extended class 
D)  child class

Question 2

If a base class and a derived class have methods with the same names but different parameter lists, the derived class method overrides the base class method.

Accepted Answer

A) True 
 B)False

Question 3

In C#, any class you create is derived from what single built-in class?

Accepted Answer

A)  System.Console 
B)  System.Object 
C)  System.Class 
D)  Object.System

Question 4

On some occasions, you might want to access parent class data from a child class.Declaring the parent class field as public would violate the principle of information hiding, but declaring it private would make it inaccessible.How can the proper level of security be achieved?

Accepted Answer

The answer of On some occasions, you might want to...

Question 5

What method can you use to return a unique hash for different objects, so long as you explicitly implement it in a derived class?

Accepted Answer

A)  CalcHash() 
B)  GetHashGen() 
C)  ToHash() 
D)  GetHashCode()

Question 6

In the event that a method that should be overridden in a child class has its own implementation, what should you declare the base class method to be?

Accepted Answer

A)  abstract 
B)  virtual 
C)  valid 
D)  static

Question 7

When using a derived class that contains a method that overrides a parent class method, what keyword can you use to access the parent class method from within the derived class?

Accepted Answer

A)  base 
B)  super 
C)  upper 
D)  parent

Question 8

Reusing existing classes and interfaces makes the job of programming easier.What are some of the future advantages that come from writing extendable base classes?

Accepted Answer

The answer of Reusing existing classes and interfaces makes the...

Question 9

System.Console is an example of a class that can't be extended.What is the reason for this?

Accepted Answer

A)  The class has a private access modifier. 
B)  The class has an internal access modifier. 
C)  The class has a static access modifier. 
D)  The class has a protected access modifier.

Question 10

You can assign a derived class object to an object of any of its superclass types.When you do, what type of conversion occurs from the derived class to base class?

Accepted Answer

A)  explicit 
B)  implicit 
C)  real 
D)  strong

Question 11

What can be used as a type of "fingerprint" for an object, due to the fact that it is unique?

Accepted Answer

A)  property 
B)  hash code 
C)  derived code 
D)  new property

Question 12

What kind of a class might be considered to be "fragile"?

Accepted Answer

A)  A built in class that is overloaded. 
B)  A class that depends on being passed parameters from another method. 
C)  A class that depends on field names from parent classes. 
D)  A class that has no destructor method.

Question 13

Show an example of a class definition that creates a subclass of an existing Employee class, and adds a private double field called commissionRate.What is the total set of fields that an instance of the new class contains?

Accepted Answer

The answer of Show an example of a class definition...

Question 14

What keyword always refers to the superclass of the class in which you use it?

Accepted Answer

A)  super 
B)  parent 
C)  upper 
D)  base

Question 15

When all base class constructors require arguments, you must include a constructor for each derived class you create.Why?

Accepted Answer

The answer of When all base class constructors require arguments,...

Question 16

What type of method has no method statements, and requires the use of an override statement for any class derived from a class that contains it?

Accepted Answer

A)  concrete 
B)  overloaded 
C)  abstract 
D)  overridden

Question 17

What happens when you declare a property defined in a base class as override in a derived class?

Accepted Answer

A)  The new declaration is eliminated in favor of the old declaration. 
B)  The new declaration removes the old declaration at compile time. 
C)  The new declaration is used when the compiler deems it appropriate. 
D)  The new declaration overrides and hides its counterpart in the parent class.

Question 18

What statement regarding the use of the Object class and classes in general is accurate?

Accepted Answer

A)  When you create any child class, no inheritance occurs automatically. 
B)  All classes inherit the Object class methods. 
C)  The object class contains a constructor, destructor, and two public instance methods. 
D)  Although every class descends from Object, not all objects are Objects.

Question 19

A superclass contains all the fields and methods of its subclasses as well as its own more specific fields and methods.

Accepted Answer