A pie chart visualizes the top 10 countries by deaths from air pollution in 2020. Each slice’s size corresponds to the death count, with labels showing values in thousands. The visualization uses D3.js (v5) to fetch CSV data, compute pie arcs, and render an SVG. It employs `d3.pie`, `d3.arc`, and `d3.scaleOrdinal` for coloring, alongside custom legend rendering with rectangles and text.