This example shows a smiley face rendered as a React component using SVG. The face consists of a yellow circle, two eyes, and a mouth, all positioned relative to the center of a 960×500 viewport. The code uses `ReactDOM.render` to mount the component and `d3.arc()` to generate the mouth’s path curve. D3 v5’s arc generator defines the mouth’s inner and outer radii and its start and end angles, while React’s JSX handles the SVG elements and attributes like circle coordinates and stroke styling.