This interactive scatter plot visualizes the classic Iris dataset, allowing users to dynamically select which sepal or petal measurements to plot on the x- and y-axes via dropdown menus. Dots representing individual flowers are color-coded by species (setosa, versicolor, virginica). The visualization is built with D3 v5, using `scaleLinear`, `axisBottom`, and `axisLeft` to render axes, and employs smooth `transition().duration(1000)` animations to transition points between axis configurations.