What happens to a class marked as sealed?

A class marked as sealed cannot be inherited by any other class. This means that no subclasses can be created from a sealed class, which enforces encapsulation and prevents further modification of its behavior through inheritance. This is particularly useful when you want to define a class that should have a fixed implementation and should not be extended or altered in unexpected ways.

Sealed classes are often used when a developer wants to control the hierarchy of classes for better maintainability and clarity in the codebase. By preventing inheritance, you ensure that the sealed class and its members maintain their intended functionality without outside interference or modification.

Other options suggest allowing some form of inheritance or overriding, which contradicts the purpose of sealing a class. Therefore, the emphasis of a sealed class is on restricting extensions and preserving its integrity within the code structure.