A modular React smiley face built with reusable SVG components, rendered through three separate files: a yellow circular background with a stroke, two eyes positioned symmetrically, and a mouth drawn using the `d3.arc` API from D3 v6. The components accept numeric props for size and positioning, and the main `App` function composes them inside an SVG element centered on a 960x500 canvas, using ES6 module imports to organize the code. The project runs with React 17 and D3 6.5, loaded via a bundled script.