Which detail presents the perspective of standing inside the Wendy's dining area looking south?

The correct choice provides a specific visual representation that aligns with the perspective of someone standing inside the Wendy's dining area and looking south. It is essential to identify details in architectural drawings and how they relate spatially to the perspective in question. In this case, detail A-3, detail 3 likely includes key visual elements and orientations that effectively convey the view from that specific vantage point. This means it captures the layout, important fixtures, and design aspects that one would see when positioned in the described location, which enhances understanding of the restaurant's interior from that viewpoint.

In architectural practice, being able to discern and interpret these details is a critical skill, as it informs how space is experienced and utilized. The other options may not provide the right orientation or perspective as required, which is why they do not fit the specific context of looking south from within the dining area.