This visualization shows the distribution of survey respondents across academic years using a pie chart, with each slice color-coded using `d3.schemeCategory10`. The code groups the mental health survey data by academic year through `d3.rollups`, sorts the categories, and renders the chart with `d3.pie` and `d3.arc` generators. A legend positioned at the top-right maps each color swatch to its corresponding academic year label. The SVG elements are sized dynamically to the container’s dimensions via `container.clientWidth` and `container.clientHeight`.