Which of the following terms describes a systematic transformation of the Earth's spherical surface onto a flat plane?

The term that describes a systematic transformation of the Earth's spherical surface onto a flat plane is "projection." In GIS and cartography, a projection refers to the mathematical process used to convert three-dimensional geographic data into a two-dimensional format that can be represented on a flat surface, such as a map. This transformation is essential because the Earth is roughly spherical in shape, and accurately representing this curvature on a flat surface requires various projection techniques that deal with distortions in area, shape, distance, and direction.

Projections are critical for spatial analysis and map-making, as they allow users to visualize and analyze geographical data in a way that is understandable and usable. Different projections serve different purposes and can highlight specific geographic features or data relationships depending on how the projection is designed.

Other terms presented, such as georeferencing, refer to the process of linking spatial data to geographic coordinates; digitizing pertains to the conversion of analog data into a digital format; and cartography is the art and science of map-making itself. While these concepts are related to GIS, they do not specifically describe the transformation of the Earth's surface to a flat plane, which is uniquely captured by the term "projection."