This bar chart displays average marks for several subjects, calculated from a CSV dataset of student scores. Each bar represents a subject, with height encoding the mean value, shown via steelblue rectangles that turn orange on hover. Built with D3.js v6, it uses `d3.csv`, `d3.mean`, `d3.scaleBand`, `d3.scaleLinear`, and axis generators to render an SVG with rotated category labels, titled “Average Marks in Each Subject.”