Which of the following is true about abstract classes?
A) they are the same as a class interface
B) the are always a subclass of a superclass
C) they are not normally instantiated in client applications
D) they are used as concrete classes by client applications

Question

Quizplus · Accepted Answer

Abstract classes are designed to be extended by subclasses and provide a common interface for those subclasses. They cannot be instantiated on their own, and are often used as building blocks for other classes. Option A is incorrect because there is a difference between an abstract class and an interface in terms of implementation. Option B is incorrect because an abstract class may or may not have a superclass. Option D is incorrect because abstract classes cannot be used as concrete classes, as they are incomplete and must be extended by a subclass before they can be used.

Which of the Following Is True About Abstract Classes