This scatterplot displays the relationship between miles per gallon and horsepower for vehicles in the auto-mpg dataset, loaded via d3.csv. The React component renders SVG circles for each data point using d3.scaleLinear for both axes. An interactive dropdown lets the user switch between years, though the code only changes state without filtering the visualized data. Axis components construct tick marks and labels, while the Marks component maps each row’s mpg and horsepower values to circle positions.