Extreme programming expresses user requirements as stories, with each story written on the card. Consider the advantages of this approach to requirements description. Below is the list of correct/incorrect answers. 1. They represent real situation that commonly arise so the system will support the most common user operations. 2. It is easy for users to understand and critique the stories. 3. They represent increments of functionality-implementing a story delivers some value to the user. 4. They focus on functional requirements rather than non-functional requirements.