This choropleth map shows the percentage of adults with a bachelor’s degree or higher across U.S. counties for the 2016–20 period, using a color-encoded geographic visualization. The map is rendered with D3 v7, specifically utilizing `d3.geoPath` to project and draw county boundaries from a TopoJSON file, while county data is loaded from a CSV via `d3.csv`. The code iterates through both datasets to match FIPS codes and assigns each county’s property value, which is then used to drive the map’s choropleth coloring.