This example shows a yellow smiley face drawn as an SVG graphic, built with React components and D3’s arc generator for the mouth. The face includes a circular head, two eyes, and a curved mouth, all positioned using D3’s arc function with specified inner and outer radii and start/end angles. React renders the SVG elements declaratively, while D3 (v5) computes the path data for the mouth arc. The code uses `ReactDOM.render` to mount the app and D3’s `arc()` API to define the mouth’s shape.