A yellow smiley face is drawn with SVG shapes: a circular head, two eyes, rectangular eyebrows, and an arc-based mouth. The code demonstrates fundamental D3.js DOM manipulation and selection, using `d3.select` to append elements and `d3.arc` for the mouth path. Animated eyebrows move up and down via chained `transition()` calls with `attr` tweening over two-second durations, showcasing D3’s built-in animation capabilities without external data.