A yellow smiley face rendered in SVG, composed of a filled circle head, two filled eye circles, and a black arc-shaped mouth. The example demonstrates how React components can generate D3-generated path data, with the mouth created using the `d3.arc` API. The visualization is built with React 16.9 and D3 v5, where React handles the SVG element structure and D3 computes the mouth’s path coordinates. The face is centered in a 960-by-500 viewport with a thick black stroke.