This example renders two identical smiley faces side by side using React and D3 v7’s `arc` generator for the mouth paths. Each face is composed from reusable components: a radially gradient-filled `circle` for the face, two `ellipse` eyes, and a multi-path mouth with rounded corners. The faces are drawn in SVG within a centered `<g>` transform, with fixed dimensions and stroke widths passed as props. The code demonstrates modular composition of geometric shapes and D3’s arc API for curved path generation.