This scatterplot visualizes the Iris flower dataset, plotting petal length against sepal width for individual flowers. The code uses React to render an SVG with D3 scales and axes, loading data asynchronously via `d3.csv`. The `Marks` component draws circles for each data point, with tooltips via SVG `<title>` elements. Axes are built from D3 linear scale ticks, with formatted labels using `d3.format`.