A smiling face rendered with SVG shapes animates its eyebrows in a looping bounce. The example uses D3.js v5 selections and transitions to build the face from circles, rectangles, and an arc path for the mouth. The `arc` generator creates the smile, while chained `transition` calls with specified durations move the eyebrow group and apply rotations. The React framework wraps the D3 code, which targets an SVG element sized 960 by 500.