A smiley face built with SVG shapes, rendered entirely through React components and D3’s arc generator. The code defines a yellow background circle, two fixed-position eyes, and a mouth created using the `d3.arc()` API with specified inner and outer radii plus angular extents. The React app imports `arc` from D3 v7, mounts to a root div, and centers elements via a `translate` transform on a group. No external data is loaded; the visualization is purely geometric and static.