This choropleth map displays country-level economic classifications using a natural Earth projection, with a color-coded legend that filters the map when clicked. The visualization uses D3 v5’s `geoNaturalEarth1` and `geoPath` to render geographic features from TopoJSON world-atlas data, while `scaleOrdinal` and `schemeSpectral` assign colors. Clicking a legend item dims non-matching countries and highlights the selected category; hovering reveals country names and values via SVG `<title>` elements. Pan and zoom are enabled through the `zoom` behavior.