This example renders a smiley face using React components and SVG primitives. It shows a yellow circle with two eyes and a curved mouth, all positioned relative to the center of a 960×500 coordinate space. The code employs React functional components for the background, eyes, and mouth, with the mouth using the d3.arc() API to generate a path. D3 v7 and React 17 are loaded via CDN, and the SVG is drawn directly into the DOM.