This example demonstrates how to create a responsive SVG visualization using D3 v7. It displays five small rectangles positioned horizontally within a 400x400 viewBox, with each rectangle’s x-coordinate determined by its data value. The code uses `d3.select` to append an SVG element and applies the `viewBox` and `preserveAspectRatio` attributes to ensure the graphic scales proportionally to its container. The rectangles are bound to the array `[1,2,3,4,5]` using D3’s data join pattern with `selectAll`, `data`, and `enter`.