A smiling face is drawn with orange and pink circles, built incrementally in SVG using D3 v5 API calls like `select`, `append`, and `attr`. The code creates each facial feature as a separate circle, then animates a path-based mouth using `d3.arc` to generate its shape, followed by chained `transition` calls that move it down and back over four seconds. The example runs in a React framework and uses only hardcoded geometry, with no external data source.