This visualization displays a horizontal bar chart of the top 20 countries by COVID-19 case counts, using data from a CSV file loaded via d3.csv. The chart maps country names on a d3.scaleBand y-axis and case numbers on a d3.scaleLinear x-axis, with blue bars and gridlines rendered as SVG elements. The React component fetches the data asynchronously, parses numeric values, and uses d3’s max function to set the x-domain, while y-axis labels and ticks are manually positioned using SVG text and line elements.