This example shows a horizontal bar chart of population data for ten countries, using the United Nations World Population Prospects 2019 dataset. The chart displays each country’s population for 2020 using SVG rectangles scaled by `d3.scaleLinear` and positioned with `d3.scaleBand`. The React components render the axes and marks, with `d3.csv` fetching the dataset and `d3.max` determining the x-axis domain. The visualization highlights a modular refactoring approach where axis and mark components are separated for clarity.