A horizontal bar chart displays the 20 most populous countries in 2010, sorted in descending order, using steelblue bars. The chart is rendered as an SVG with D3 v7, employing `d3.scaleLinear` for the x-axis, `d3.scaleBand` for the categorical y-axis, and `d3.axisBottom` and `d3.axisLeft` for tick marks. Population data is loaded from a remote CSV file via `d3.csv`.