A smiling face rendered as a yellow circle with black stroke, two eyes, and a halfway smile (an arc from 180° to 270°). The face is drawn with React components using SVG, with each facial feature (background, eyes, mouth) as a separate reusable component. It uses d3.arc to generate the mouth’s path, and d3 is loaded alongside React 17 and D3 v7. The face’s dimensions and proportions are passed as props from index.js.