This example demonstrates fundamental DOM manipulation with D3.js by building a yellow smiley face with eyes, eyebrows, and a mouth. The code appends SVG circle and rectangle elements to a central group, then animates the eyebrows upward and back down using chained `transition` calls with a 2-second duration each. The mouth is drawn with the `d3.arc` generator using specified inner and outer radii and start/end angles. All elements are positioned via explicit pixel coordinates within a 960-by-500 SVG canvas.