Which keyword allows the use of a superclass constructor?

• A. this()
• B. super()
• C. final()
• D. abstract()

Answer: (B)

In Java, the keyword that allows the use of a superclass constructor is "super()". When a class inherits from a superclass, the subclass can invoke the constructor of its superclass using the super keyword. This is particularly useful when the superclass has fields that need to be initialized when creating an instance of the subclass.

The syntax super() is typically placed as the first statement in the subclass constructor. This ensures that the superclass constructor is executed before any other code in the subclass constructor runs. This is essential for properly setting up the inherited attributes from the superclass before performing subclass-specific initialization.

Using super() also allows access to constructors of the superclass that may take arguments, providing flexibility in how the subclass can be initialized.

Other keywords associated with the choices do not serve this purpose. For instance, "this()" is used to invoke another constructor in the same class, while "final" and "abstract" are used to declare classes, methods, or variables with specific behaviors related to inheritance and method overriding, but do not pertain to accessing constructors.