A yellow smiley face with black outlined eyes and a curved mouth is rendered as an SVG inside a React application. The code splits the face into separate ES6 module components, including `BackgroundCircle`, `Eyes`, and `Mouth`, using React fragments. The `Mouth` component uses the `arc` function from `d3` to define its path, while fixed numeric constants set the face dimensions. This example demonstrates modular component reuse with React and D3.