What mapping tool should students use to help viewers understand their wall display of Texas?

The most appropriate choice for helping viewers understand a wall display of Texas is a map legend. A map legend provides essential information that explains the symbols and colors used on the map, making it easier for viewers to interpret the data presented visually. It connects the visual representation with its meaning, ensuring that someone looking at the wall display can understand what various elements signify, such as different geographical features, towns, or areas of interest.

While a map key and a map legend might seem similar, a map key typically refers to the specific list of symbols and their meanings rather than the comprehensive guide that a legend usually encompasses. Additionally, pie charts and graphs serve different purposes in data representation. Pie charts display parts of a whole, and graphs show relationships between data points. They do not specifically aid in interpreting a map's visual data as effectively as a legend does.