A yellow smiley face with animated eyebrows demonstrates basic D3.js DOM manipulation. The face is drawn entirely with SVG primitives—a circle for the head, smaller circles for the eyes, rectangles for the eyebrows, and a path generated by `d3.arc` for the mouth. Using `d3.transition` with a two-second duration, the eyebrow group repeatedly shifts vertically, creating a bobbing motion. The code leverages D3 selections and attribute setting to build the static facial features, then applies chained transitions to animate the eyebrows independently of the rest of the face.