Mastering Java: The Ultimate 2026 All-In-One Quiz to Excel in 'Thinking in Java

Option A is incorrect because a private constructor does not necessarily prevent subclassing, it only restricts direct access to the constructor. A subclass could still access the superclass' private constructor through a public or protected method.

Option B is incorrect because static factory methods can be implemented using public constructors.

Option C is incorrect because a private constructor does not necessarily mean the class can only be instantiated from inside the class. Other static methods in the class could also create an instance using the private constructor.

A private constructor may be used for a combination of these reasons, but not exclusively for any one reason.