A smiling face drawn with React SVG components follows the mouse cursor across the screen. The face is composed of reusable React components (BackgroundCircle, Eyes, Mouth) that use d3.arc for the mouth path. The app tracks mouse movement via React’s onMouseMove and useState hook, updating the circle’s cx and cy coordinates in real time. The visualization demonstrates interactive, state-driven rendering with React 17 and d3.v7, tightly coupling user input to SVG output.