A React component uses SVG to render a single circle that tracks the mouse cursor across a 960-by-500 viewport. The `useState` hook stores the cursor’s x and y coordinates, initialized at the center, while the `useCallback` hook wraps the `handleMouseMove` event handler to update that state on every mouse movement. The circle’s `cx` and `cy` attributes are bound to the stored coordinates, and the SVG element’s `onMouseMove` prop triggers the update. This example demonstrates interactive state management and event handling within a React-driven SVG visualization.