Final answer:
A large-scale map is best for showing detailed features of a small area, such as the streets of Portland, as opposed to large geographic features or entire cities.
Step-by-step explanation:
A large-scale map would be used to show detailed features of a smaller area. In the context of the options provided, large-scale maps are most suitable for showing fine details such as the streets of Portland. Large-scale maps give an up-close view, allowing the viewer to see streets, buildings, and sometimes even individual trees or houses. They would not be as useful for showing larger geographic features like the five Great Lakes, the location of an entire city such as Las Vegas, Nevada, or extensive mountain ranges like the Appalachian Mountains, as these require a small-scale map to represent the broad area.