This example shows a static smiley face drawn with React and D3, using the D3 arc generator to create the mouth shape. The face is positioned at the center of a 960-by-500 pixel canvas, with circular eyes and a thick, arc-based mouth spanning a half-circle. The code integrates React components with D3’s `arc()` API, while ReactDOM renders the root element into the page. The app currently displays only a “Hello World” text placeholder, as the smiley face visualization is not yet implemented in the rendered output.