Which of the following statements about a non-public class is true?

• A. A non-public class can be accessed from any package
• B. A non-public class is only accessible within its package
• C. A non-public class can only have private members
• D. A non-public class can never be instantiated

Answer: (B)

A non-public class, often referred to in Java as a package-private class, is indeed only accessible within its own package. This means that other classes defined in the same package can freely access it, but classes outside of that package cannot. This encapsulation is an important aspect of Java's access control, allowing developers to control visibility and protect the internal implementation details of their classes.

The other options contain inaccuracies about the characteristics of a non-public class. For instance, the claim that a non-public class can be accessed from any package is incorrect since it specifically restricts access to classes within the same package. Similarly, the statement about private members is misleading; while non-public classes can have private members, they are not limited to that only and can also include public or protected members. Lastly, a non-public class can indeed be instantiated, which contradicts the claim that it can never be instantiated. All of this firmly supports the understanding that a non-public class's scope is confined to its package, allowing for better modular design in Java applications.