This bubble chart visualizes the relationship between population, GDP, and life expectancy for 15 countries, with each country represented by a colored circle. The x-axis shows GDP in USD, the y-axis shows population, and bubble size encodes life expectancy. Built with D3 v7, the visualization uses `d3.scaleLinear` for axes and bubble sizing, `d3.scaleOrdinal` with `d3.schemeCategory10` for colors, and includes interactive tooltips on mouseover. SVG circles are rendered with animation-ready styling, and a legend illustrates life expectancy values.