Which pattern defines an interface for creating an object, letting subclasses decide which object to instantiate?

The Factory Method Pattern is the correct choice as it provides a way to define an interface for creating an object, allowing subclasses to override and decide which class to instantiate. This pattern encapsulates the instantiation process, promoting loose coupling in the code since the object creation logic is centralized in a method, rather than being scattered throughout the codebase.

By using the Factory Method, the client code can work with the interface without needing to know the specific classes that implement the interface. This fosters an architecture that is easier to maintain and extend, as new subclasses can be introduced without altering existing code. Each subclass can implement the creation logic differently, allowing for flexibility in how objects are created based on context or configuration.

In contrast, the other patterns mentioned operate differently. The Abstract Factory Pattern typically involves creating a set of related or dependent objects across multiple product families. The Builder Pattern focuses on constructing a complex object step by step, separating the construction process from the representation. The Chain of Responsibility Pattern is aimed at passing requests along a chain of handlers, without requiring the sender to know which handler will process the request.

Thus, the key characteristic of the Factory Method Pattern is its focus on the instantiation decision encapsulated within the subclass, which aligns perfectly with the question