A cheerful smiley face with moving eyebrows demonstrates fundamental D3.js DOM manipulation. The SVG face, drawn with circles and rectangles, animates its eyebrows up and down using chained `transition()` calls. Built with D3 v5, the code uses `select`, `append`, and `attr` to construct elements, while the `arc()` generator creates the mouth path. The face centers itself dynamically using the SVG's width and height attributes, and a pink background fills the canvas.