The correct answer is A. Methods.
Methods are operations that the object is capable of performing. They are defined by the class of the object and are used to interact with the object. Methods can be called by other objects or by the object itself.
B. Events are occurrences that happen to an object. They can be caused by the user, by other objects, or by the system itself. Events can be used to trigger methods or to change the state of the object.
C. Instances are specific objects that are created from a class. Each instance has its own unique set of attributes and methods.
D. Attributes are properties of an object. They describe the state of the object and can be used to interact with the object.