A line chart displays total sales for each discount level in the Superstore dataset. The chart uses a linear x-axis for discount values and a linear y-axis for summed sales, with a steelblue line connecting the aggregated points. Built with D3 v7, the code employs `d3.csv`, `d3.rollups` for grouping by discount, `d3.scaleLinear` for axes, and `d3.line` to generate the path. The SVG renders with explicit margins and axis labels for "Discount" and "Total Sales."