A smiley face drawn with SVG shapes animates its eyebrows upward and back down in a looping transition. The example demonstrates fundamental D3.js DOM manipulation by building a green circle, white eyes, rectangular eyebrows, and an arc-based mouth using `d3.select` and `d3.arc`. Animated with chained `transition.duration` calls, the eyebrows shift via `attr` transforms. Rendered in an SVG container sized 960 by 500, the code uses D3 v5 and imports `select` and `arc` directly from the library.