Typing Conversions - Quiz Explanation
The answers you selected are indicated below, along with text that explains the correct answers.
1.
In a class hierarchy defined by public inheritance that creates a related set of user types, __________ may be used to point to any of the objects.
A.
a derived class pointer
B.
a char* pointer
C.
a base class pointer
D.
any pointer declared in any of the classes in the hierarchy
The correct answer is C.
In a class hierarchy defined by public inheritance that creates a related set of user types, a base class pointer may be used to point to any of the objects.
2.
The relationship between __________ and its subtype is called an ISA relationship.
A.
a privately inherited class
B.
a publicly inherited class
C.
a protected inherited class
D.
any inherited class
The correct answer is B.
IS-A is the relationship between the publicly inherited class and its subtype. This is called public inheritance. In public inheritance, the protected and public members of the base class are to be inherited as protected and public members of the subtype. Base class members that are private are inaccessible to the subtype.
3.
A constructor in the base class:
A.
must be explicitly called by the derived class constructor
B.
is implicitly called by all derived class constructors with the same parameter list
C.
must be repeated (copied) into the derived class if it is needed
D.
may not be invoked explicitly
The correct answer is A.
A constructor in the base class must be explicitly called by the derived class constructor.