A good answer might be:

The Object class.

In Java, there is a pre-defined class that is the ultimate ancestor of all other classes. This class is called Object. Object defines the basic nature of all Java objects; much of what goes on behind the scenes when a Java program is running is defined by Object.

So, for example a small part of the Java class hierarchy looks like this:

The "clouds" convey the idea that these are class definitions, not objects. The outline of the Component class is dotted to show an abstract class. This shows that the classes Boolean, Character, Component, String, and many others have Object as a direct ancestor.

QUESTION 2:

(Review: ) can a child class add its own methods and variables to those it inherits from its parent?