Answer: (iii) Runtime polymorphism

Explanation

Dynamic method dispatch selects which overridden method to call based on the actual (run-time) type of the object, not the declared type of the reference.

Compilers implement it with a virtual method table (vtable): each object carries a hidden pointer to its class's vtable, and a virtual call becomes an indirect call through a fixed slot index.

Animal a = new Dog();
a.speak();   // Dog.speak() is chosen at run time

This is exactly runtime (dynamic) polymorphism. It has nothing to do with lexical analysis, constant folding or register allocation.

$$\boxed{\text{(iii) Runtime polymorphism}}$$