Fruit icons transition smoothly between enter, update, and exit states as apples are eaten and one apple changes into a lemon. The visualization demonstrates d3's data join pattern with key-based binding, using `selection.enter()`, `selection.merge()`, and `selection.exit()` to manage SVG circles. Each state change triggers a 1000ms `transition()` that animates the circles' radii, positions, and fill colors, with colors and sizes derived from ordinal scales mapping fruit types to values.