This bar chart displays the average marks for each age group from 18 to 69, sourced from the attend_data.csv file. It uses D3 v4 with SVG rendering and animated transitions, where bars sequentially grow in height. Hovering over a bar triggers a mouseover event that highlights it in orange, enlarges it, and displays its exact value, while mouseout restores the original state. The chart includes axes with percentage tick labels and custom styling.