Select one or more Y columns (or a range of one or more Y columns). If there is an associated X column, X column supplies X values; otherwise, sampling interval of the Y column or row number is used.
Select desired data.
Select Plot > Specialized : Line.
Click the Line button (stock chart group) on the 2D Graphs toolbar.
StockLine.otp (installed to the Origin program folder).
The (stock) Line graph template is slightly customized for plotting financial data: