This example demonstrates a simple animated sine wave created with D3 version 7, rendering fifteen circles along a horizontal axis that oscillate vertically over time. Using `d3.select`, `d3.range`, and the `join` pattern, the code updates circle positions inside a `setInterval` loop at roughly 60 frames per second. The visualization shows how D3’s data join handles dynamic updates efficiently, with each circle’s Y coordinate computed from a sine function offset by a time variable.