This bubble chart visualizes the correlation between GDP per capita, life expectancy, and population area ratio across 20 countries, with each bubble’s size encoding population density and color identifying the country. The chart uses d3.csv() to load data from bubblechart.csv and renders circles via d3.scaleLinear for axes and bubble sizing, with a d3.scaleOrdinal and d3.schemeCategory10 for color mapping. Interactive tooltips are implemented with D3 event handlers (mouseover, mousemove, mouseleave) that display country details, while a static legend lists all countries beside color-coded dots.