This example demonstrates how to build a simple smiley face using React and D3. It renders a yellow background circle and a mouth path formed with a D3 arc generator, all positioned within an SVG coordinate system. The code uses React functional components to structure the drawing, while D3’s `arc()` API defines the mouth’s inner and outer radii and angular extent. The face is centered via an SVG group translation, and the result is a static, reusable visualization of basic geometric composition.