An interactive dropdown menu for selecting a pet is rendered with React and ReactDOM. The component manages its own state via the `useState` hook, updating the selected value and logging it to the console whenever the user changes the option. A custom `Dropdown` component maps over a static array of pet options to generate the `<select>` element, and the selection is controlled by `onSelectedValueChange` callbacks. The interface is styled with CSS, and the example uses React 16.9.0 from the unpkg CDN.