Choice "C" is correct. The permanent file includes items with continuing audit significance, such as debt agreements.
Choice "b" is incorrect. Lead schedules would be included in the current audit documentation since they are applicable to the current year's audit only.
Choice "a" is incorrect. Attorney's letters would be included in the current audit documentation since they are applicable to the current year's audit only.
Choice "d" is incorrect. Bank statements would be included in the current audit documentation since they are applicable to the current year's audit only.