A smiling face rendered in SVG using React components and D3’s `arc` API for the mouth. The face is centered within a fixed 960×500 viewport, with a yellow background circle, two black eyes, and a curved mouth generated by an arc path. Layout constants for eye offset, radius, and stroke widths are passed as props to modular React components. D3 v5 supplies the arc generator, while React handles component composition and rendering into the SVG DOM.