This example uses D3.js to build a smiley face directly in SVG, with animated eyebrows that move up and down in a repeated cycle. It demonstrates basic DOM manipulation by creating circles for the eyes and face, rectangles for the eyebrows, and an arc path for the mouth using D3’s `arc()` helper. The animation relies on chained `transition().duration()` calls to shift the eyebrows’ vertical position. The code explicitly imports `select` and `arc` from D3 and renders everything within a 960x500 SVG canvas.