A line chart tracks population growth over time, using a blue stroke to connect annual data points from a CSV dataset. The visualization relies on D3 v7 to load the external population.csv, parse numeric values for year and total_population, and render an SVG with linear scales for the axes. The code constructs a line generator, applies it to a path element, and adds axis groups with tick labels, with the y-axis scaled from zero to the maximum population value.