This line chart shows the life expectancy of the USA from 1800 to 2016, with the years on the x-axis and expectancy values on the y-axis. The React-based visualization uses D3 v5 scales and the `d3.line` generator to create the SVG path, with axes rendered via `d3.axisBottom` and `d3.axisLeft`. Data is loaded from a CSV file using `d3.csv` and parsed with `d3.timeParse`. Gridlines, axis labels, and a green stroke line are styled through CSS.