A menu built with React lets a user select a pet from a dropdown list of six options. The example demonstrates a reusable `Dropdown` component that receives an array of option objects, an identifier, the currently selected value, and a callback for selection changes. The component renders a `<select>` element whose options are mapped from the data, marking the chosen value as selected. State management is handled through React's `useState` hook in the `App` component, passing the selected value to the component. The example uses React DOM for rendering, with the interface styled via the page's inline CSS.