This interactive scatterplot lets users explore relationships between variables in the auto-mpg dataset by selecting which columns to plot on the x- and y-axes via dropdown menus. The menus trigger re-renders that update the axes, labels, and animated circle positions. The visualization uses D3 v5 with the `scaleLinear`, `extent`, `axisLeft`, and `axisBottom` APIs, and the dropdown menu component is a custom reusable module. SVG circles transition smoothly over 2 seconds when data changes.