A yellow smiley face is rendered on an SVG canvas using React components. The face is composed of a filled circle for the background, two circles for the eyes, and a D3-generated arc for the mouth, implemented with `d3.arc()` to define the path. The React component structure (`Face`, `BackgroundCircle`, `Eyes`, `Mouth`) parameterizes positions and sizes, while `FaceContainer` manages the SVG and coordinate translation. The example demonstrates declarative composition of SVG primitives and D3 geometry within a React application.