This example uses a dual-axis line chart to compare the daily closing and opening prices of a financial dataset from April to May 2012. The SVG rendering is built with React and D3 v4, using scales such as `d3.scaleTime` and `d3.scaleLinear` along with `d3.line` and `d3.axisLeft`/`d3.axisRight`. Two paths are drawn: one steelblue line for `close` and a red line for `open`, each with its own y-axis scale. Data is loaded from a CSV file via `d3.csv` and parsed with `d3.timeParse`.