This example demonstrates a minimal React application rendering a static “Hello” message, showing how D3 can be loaded alongside React in a single project. The code imports React and `createRoot` from `react-dom` to mount the `App` component into the `#root` element, while D3 v7 is included via external script tags in `index.html` but is not yet used for any visualization. The styling applies a large centered font size to the message, serving as a basic starter template for integrating D3 with React.