A yellow smiley face is drawn in an SVG using React components and D3's `arc` generator to create the mouth. The face consists of a large yellow circle with a black stroke for the outline, two black eye circles positioned symmetrically, and a semi-circular mouth path. D3 v7 calculates the mouth arc with specified inner and outer radii and angles, while React manages the SVG element hierarchy and attribute bindings for a declarative rendering approach.