This example shows a scatter plot of the classic Iris dataset, mapping sepal length on the x-axis and sepal width on the y-axis. Clicking a circle highlights it with a white fill, bold stroke, and pointer cursor. Built with React and D3 v7, the visualization uses `d3.csv` to load data, `scaleLinear` and `extent` for scales, and `axisBottom`/`axisLeft` for axes. SVG circles are rendered via data joins with click event handlers, while a ResizeObserver tracks container dimensions for responsive sizing.