This example builds a simple cartoon face using D3.js v5 and SVG. It draws a yellow circle for the face, two black circles for eyes, and an arc-based path for the mouth, all positioned relative to the SVG’s width and height attributes. The code uses `d3.select`, `.append`, and method chaining with `.attr` to set geometry. The mouth is created with `d3.arc()`, specifying inner and outer radii and start/end angles, then applied to a `<path>` inside a translated `<g>` element.