This example demonstrates fundamental DOM manipulation with D3.js by rendering a static smiley face in SVG and animating its eyebrows. The face is built from primitive shapes—circles for the eyes, rectangles for the eyebrows and hair, and a path generated with the `arc()` function for the mouth—all positioned within a centered `<g>` element. Using `transition.attr`, the eyebrows move upward and then return to their original position over repeated two-second intervals. The code relies on `d3.select`, `d3.arc`, and chained transitions to create the looped motion.