This example demonstrates how to create a choropleth map of U.S. counties using D3.js. It renders an SVG projection of the United States with a light background, then overlays county boundaries and merges them with education data loaded from freeCodeCamp’s testable projects API. The code uses `d3.geoAlbersUsa` for the projection, `d3.geoPath` to generate paths, and TopoJSON’s `feature` method to extract county geometries. Education statistics are fetched in parallel with county boundaries via `Promise.all`. The resulting visualization shows county outlines but does not yet color them by data values.