In the hierarchy of classes, which statement is true about the class lcl_plane and its subclasses lcl_passenger and lcl_cargo?

In object-oriented programming, particularly in the context of ABAP, the concept of inheritance allows a subclass to be treated as an instance of its parent class. This particularly applies to the scenario involving the class lcl_plane and its subclasses lcl_passenger and lcl_cargo.

When an instance of lcl_passenger is created, it inherits the properties and methods of lcl_plane since lcl_passenger is a subclass of lcl_plane. Consequently, because of this inheritance, any instance of lcl_passenger can indeed be treated as an instance of lcl_plane. This is a fundamental feature in object-oriented programming known as polymorphism, which allows you to use a subclass instance wherever a parent class instance is expected.

This flexibility is essential in design as it enables developers to write more general code that can operate on the class as a whole (the parent class) rather than specifics of the subclasses. It promotes code reusability and efficiency.

To summarize the nature of the other statements:

• The second statement about assigning an instance of lcl_passenger to a reference variable of type lcl_cargo is not valid, as `l