A React component uses the `useState` hook and a reusable `Dropdown` component to render an HTML `<select>` menu for choosing a pet. The dropdown maps over a static array of pet options, displaying each as an `<option>` element. The selected value updates the React state and is logged to the console, while the `onChange` event handler triggers the state change. The example combines React 17, ReactDOM, and a minimal amount of D3 v7 for the page setup.