A cheerful smiley face rendered in SVG uses D3 v5 to draw a yellow circle as the head, two smaller circles for eyes, and an arc path for the mouth. The code imports `select` and `arc` from D3, positions the elements relative to the SVG’s width and height, and applies transforms to center the group. Eye spacing and radius are defined as constants, while the mouth uses an arc generator with fixed inner and outer radii and angle ranges. The example demonstrates basic D3 shape generation and SVG manipulation with no external data source.