This bar chart displays the population of the top 10 countries in 2010, sourced from a CSV file loaded via `d3.csv`. The chart uses `d3.scaleBand` for the categorical y-axis and `d3.scaleLinear` for the quantitative x-axis, with population values formatted using `d3.format`. Bars are rendered as SVG `<rect>` elements with built-in tooltips showing the formatted population. The visualization is built with React, using reusable axis and mark components, and styled with green bars and blue axis lines.