The visualization is a pie chart showing the top 10 countries with the highest number of deaths attributed to air pollution in 2020. Each slice is annotated with its corresponding value in thousands, and a legend on the right pairs each country name with its death count. The chart is built using D3 v5, leveraging the `d3.pie`, `d3.arc`, and `d3.scaleOrdinal` APIs for slice generation, coloring, and layout, with data fetched as CSV from a GitHub Gist. The SVG canvas is populated programmatically via `d3.select`, and text labels are positioned using the arc centroid.