This interactive scatter plot visualizes Fisher's Iris dataset, displaying the relationship between two flower measurements (from sepal length/width and petal length/width) as colored points representing the three Iris species. Users can dynamically switch which measurement appears on the x- and y-axes via dropdown menus rendered in HTML. The visualization uses D3 v5 to create an SVG canvas, with `d3.scaleLinear` for axes, `d3.axisLeft` and `d3.axisBottom` for tick marks, and `d3.scaleOrdinal` to map species to semi-transparent red, green, and blue fill colors. The code rebuilds the plot from scratch whenever an axis selection changes, removing all SVG elements and re-rendering from the source CSV data.