What does the 'this' keyword refer to in object-oriented programming?

In object-oriented programming, the 'this' keyword refers to the current instance of the class in which it is being used. This allows you to access instance variables and methods that belong to that specific object. When an object is created from a class, 'this' provides a way to differentiate between instance variables and parameters or methods that have the same name.

For example, if a class has an instance variable named 'name' and a constructor parameter also named 'name', using 'this.name' will clearly refer to the instance variable, while just using 'name' would refer to the parameter. This is crucial for writing clear and error-free code, as it maintains the context of the current object within methods and constructors.

In contrast, the other options do not accurately capture the purpose of the 'this' keyword. While the class itself can be referred to in other contexts (often using the class name), 'this' is specifically tied to the object that is currently executing the method. Therefore, understanding that 'this' points to the current instance is fundamental in object-oriented programming.