This D3.js v5 tree chart visualizes COVID-19 statistics across Asian regions, including countries like Pakistan, India, and Indonesia, with leaf nodes displaying case counts, deaths, and recoveries. The hierarchical data structure is defined in JavaScript and rendered as an SVG using the `d3.tree()` layout algorithm, which positions nodes and draws curved links between parent and child elements. Node colors and link strokes are mapped from data properties, with the entire visualization styled through an external CSS file that applies blue node outlines and green connecting paths.