This line chart displays a country's total medal count each year, with a dropdown menu to switch between countries. The visualization initially draws a line for the selected country, filtering the yearly data accordingly. The chart is built using D3.js, specifically `select`, `scalePoint`, `scaleLinear`, and `line`, along with the `responsive-axes` library for layout. The SVG is rendered directly to the container, and the dropdown listens for a `change` event to trigger a redraw with a filtered dataset.