This example presents an animated scatter plot of the Iris dataset, where users can select which quantitative attributes to map to the x- and y-axes via interactive dropdown menus. The visualization uses D3 v6 with SVG rendering, and employs the `selection.join` pattern to smoothly transition circles between positions as axis mappings change. Axes are updated using `d3.axisLeft` and `d3.axisBottom`, with `d3.transition` providing a 1000-millisecond animation effect on circle repositioning and radius growth.