This pie chart visualizes total study hours per group from a small CSV dataset, splitting respondents into Control and Treatment categories. Each slice is labeled with its percentage share, and a legend identifies group colors. The visualization uses D3 v7’s `d3.pie`, `d3.arc`, and `d3.rollup` to aggregate and compute layouts, with `d3.schemeCategory10` for coloring and `d3.format` for percentage labels. SVG rendering places the chart and legend side by side.