This example visualizes administrative divisions of Bangladesh, displaying the country’s seven major regions as a purple choropleth map. Each region, when hovered, reveals a tooltip with its name and area in square kilometers, sourced from a local `countryData.json` file. The map is rendered using D3’s `geoMercator` projection and `geoPath` generator, with geographic boundaries parsed from a TopoJSON file via the `topojson` feature function. The visualization supports interactive zooming, implemented through D3’s zoom behavior, and uses SVG elements for rendering.