What is a significant advantage of using the virtual keyword in C++?

The virtual keyword in C++ is used primarily in the context of inheritance and polymorphism. When a method is declared as virtual in a base class, it allows derived classes to override that method with their own implementation. This means that when a base class pointer or reference points to an object of a derived class and calls a virtual method, the derived class's version of the method will be executed, not the base class's version.

This dynamic dispatch mechanism ensures that the correct method is called, reflecting the actual object type at runtime rather than the type of the pointer or reference. This is a cornerstone of achieving polymorphic behavior in C++, allowing for more flexible and maintainable code architectures, particularly in large systems where behavior can vary significantly among derived classes.

The other options do not accurately describe the function of the virtual keyword. For instance, it does not prevent method overloading, enhance performance, or automatically manage memory for derived classes. Instead, its primary role is to facilitate proper virtual function calls during runtime through the use of table lookups that ensure the correct method implementation is executed.