q
A real-time pie chart displays sales distribution across five products, with a legend and hover tooltips showing percentages. The visualization updates its data every five seconds via a simulated `d3.json` API call, animating slice transitions using `d3.pie`, `d3.arc`, and `transition().duration()`. D3 v7 renders the SVG chart and handles enter/update/exit selections, while the tooltip responds to mouse events.