A React application renders a small interactive form for choosing a pet from a dropdown menu. The selected pet’s name is displayed below the menu. The example uses React’s `useState` hook to manage the selected value, and a custom `Dropdown` component with an `<select>` element. React and ReactDOM are loaded from unpkg CDN, and the app is mounted into the `#root` div. The menu options are defined in a local array of `{ value, label }` pairs.