A multi-series combined chart displays three time-based metrics (metric_A, metric_B, metric_C) as smooth lines alongside vertical bars representing monthly averages of metric_B. The SVG visualization uses D3 v7 with d3.csv for data loading, d3.scaleTime and d3.scaleLinear for axes, d3.rollups for monthly aggregation, and d3.line with curveMonotoneX for line generation. Gridlines and a legend support the view, with data sourced from a remote CSV file.