A yellow smiley face rendered in SVG uses D3.js v5 to demonstrate basic DOM manipulation and animation. The face is built by appending circles for the head and eyes, rectangles for eyebrows, and a path generated with the `d3.arc()` API for the mouth. The eyebrows animate upward and back down over two sequential 2000-millisecond transitions, showing how `selection.transition()` chains. The code uses `d3.select` to manipulate the SVG elements and sets coordinates with fixed pixel offsets for facial features.