This example demonstrates a minimal setup for building a D3 visualization, showing a red-filled SVG canvas. The code creates a 960 by 500 pixel SVG element in the HTML file and uses D3 v4's `d3.select` to target it, then applies a red background color via the `style` method. It serves as a template for getting started with D3 in a React project, though this particular version uses plain HTML and JavaScript with no imported React components.