This example shows a simple smiley face composed of SVG shapes: a yellow circle for the head, two red circles for the eyes, and two arcs for the nose and mouth. The face is rendered with React components, using D3’s `arc` generator to create the curved paths for the mouth and nose. The SVG is drawn from a React component that maps the face’s geometry (center, radii, and offsets) into the corresponding `<circle>` and `<path>` elements.