A smiley face built with React and D3 is rendered as an SVG graphic. The visualization shows a yellow circle face with two black eyes and a curved mouth, all centered on a 960 by 500 pixel canvas. The code uses D3's `arc()` generator to create the mouth path and React to manage the SVG elements, including the `circle` shapes and the `path` for the mouth. The face is drawn using a static set of coordinates and dimensions defined in the React component.