A scatterplot displays the relationship between patient age and cholesterol levels from a heart disease dataset. Each circle represents one patient, positioned by age on the x-axis and cholesterol on the y-axis. The visualization is built with React and D3 v7, using `scaleLinear`, `extent`, and `axisBottom`/`axisLeft` to render axes and circles. Data loads from a CSV file with numeric fields formatted before the chart renders.