What is a sphere-shaped model of the Earth called?

The correct designation for a sphere-shaped model of the Earth is a globe. A globe accurately represents the Earth's shape, landforms, and geographical features in three-dimensional form, helping users visualize the planet more realistically. This spherical model allows for an accurate portrayal of distances, directions, and the relationship between various locations on the Earth’s surface.

Maps, while they depict geographical information, do so in a two-dimensional format that can distort certain elements due to the flattening of the Earth's surface. Charts generally refer to graphical representations used for navigation or data analysis, and diagrams are simplified drawings that illustrate concepts or processes. Thus, a globe stands out as the most accurate model of Earth, making it the appropriate term in this context.