This example presents an interactive scatter plot of the Iris flower dataset, allowing users to select which measurement (sepal or petal length/width, or species) appears on each axis via two dropdown menus. The visualization uses a reusable chart pattern built with D3 v6, employing the `selection.join` API to animate circle positions and radii with `transition` delays. It also demonstrates a reusable menu component that communicates changes through a custom `dispatch` event, with SVG axes that transition smoothly alongside the data points.