This example shows the classic Iris flower dataset in a basic scatter plot. It plots sepal length on the x-axis against sepal width on the y-axis, with each of the 150 data points rendered as a small black circle. The code uses React for component state and effects, while D3 v7’s `select`, `scaleLinear`, and `extent` functions handle the SVG element selection and linear scale mapping. The data is loaded from a CSV file using D3’s `csv` method and passed to a reusable `viz` function for rendering, following a clean separation between React and D3 logic.