Which statement describes the Object class in Java?

Which statement describes the Object class in Java?

• A. It is the ultimate superclass of all classes.
• B. It is an interface.
• C. It cannot be extended.
• D. It is the root of the primitive type hierarchy.

Answer: (A)

In Java, there is a single inheritance tree where Object sits at the very top. This makes Object the ultimate superclass of all classes, because every class you define, directly or indirectly, inherits from Object. That inheritance gives every object the methods defined in Object, such as toString, equals, hashCode, and getClass. Object is a real class, not an interface, so describing it as an interface isn’t accurate. It isn’t unextendable either—you can declare a class that extends Object (explicitly or implicitly, since most classes don’t specify a different superclass). Primitive types aren’t classes, and they don’t derive from Object; they have their own treatment, with wrapper classes like Integer or Double for object-oriented use, and those wrappers do extend Object. So the statement that Object is the ultimate superclass of all classes correctly captures how Java’s class hierarchy is structured.

In Java, there is a single inheritance tree where Object sits at the very top. This makes Object the ultimate superclass of all classes, because every class you define, directly or indirectly, inherits from Object. That inheritance gives every object the methods defined in Object, such as toString, equals, hashCode, and getClass.

Object is a real class, not an interface, so describing it as an interface isn’t accurate. It isn’t unextendable either—you can declare a class that extends Object (explicitly or implicitly, since most classes don’t specify a different superclass). Primitive types aren’t classes, and they don’t derive from Object; they have their own treatment, with wrapper classes like Integer or Double for object-oriented use, and those wrappers do extend Object.

So the statement that Object is the ultimate superclass of all classes correctly captures how Java’s class hierarchy is structured.