This example draws a simple yellow smiley face in SVG using React and D3.js. It defines the face shape with a React component, rendering two eye circles and a mouth arc positioned on a larger yellow circle with a black stroke. The mouth is generated by D3’s `arc` function, with specified inner and outer radii and angled start/end points. The code uses ReactDOM to mount the component into a root div, combining React’s declarative JSX with D3 v6 geometry helpers for the path data.