A scatter plot of the Iris dataset maps petal length against sepal width, with each point colored by species. Hovering over the color legend dims non-matching points, creating an interactive filter. Built with React and D3 v5, the visualization uses `scaleLinear` for axes, `scaleOrdinal` for colors, and React state to manage the hovered value. SVG circles render the data, while the legend triggers `onMouseEnter` and `onMouseOut` events to update opacity.