The event that best completes the cause and effect table, leading to the effect of many farms being foreclosed by the mid-1920s, is:
A. many farmers invested in land and equipment during the war.
This option suggests that farmers took on debt to invest during a time of high demand, which later became unsustainable when prices fell, leading to foreclosures. The other options either do not directly relate to the cause of foreclosures or describe scenarios that would not necessarily lead to widespread foreclosures by the mid-1920s.