Which of the following describes the Command pattern correctly?

Question $13$ options:

Encapsulates a request as an object, letting to parameterize clients with different requests and support undoable operations

Provides a way to access the elements of an aggregate object$-$sequentially without exposing its underlying representation

Defines a family of algorithms, encapsulates each one and makes them interchangeable

Defines a one$-$to$-$many dependency between objects so that when one object change state, all its dependents are notified and updated automatically