In Java, which keyword, when applied to a class declaration, prevents that class from being extended (inherited) by any other class?

The final keyword, when applied to a class, prevents it from being subclassed — any attempt to extend a final class results in a compilation error. static relates to class-level (rather than instance-level) members and does not restrict inheritance. private restricts the visibility of members, and is not even a valid modifier for a top-level class. abstract actually requires a class to be subclassed in order to be instantiated (the opposite effect), and protected is an access modifier controlling visibility, not inheritance eligibility.