This example renders a smiley face composed of SVG circles and an arc-shaped mouth, split across three React components. The background circle, eyes, and mouth are defined in separate files and combined in the main `App` component. D3’s `arc` generator creates the mouth path with specified inner and outer radii and start/end angles, while React fragments allow multiple eye circles without extra DOM nodes. The SVG is centered with a transformed group, and all styling (yellow fill, black stroke) is applied via JSX attributes.