This example shows a classic smiley face rendered as a composite of React components: a yellow background circle, two black eyes, and an arc-shaped mouth. Each facial feature is a separate SVG element positioned using props passed from a parent `App` component. The mouth is generated with the `d3.arc()` shape generator, while the circle and eye positions are defined declaratively via JSX. The visualization uses React for component structure, D3 v5 for the arc path calculation, and SVG for final rendering.