Which of the following statements explains why work in progress (WIP) is considered an area of high audit risk? 1 The balance is always material 2 WIP involves subjective estimation of the stage of completion 3 An independent expert might need to be used to assess its valuation 4 The process used to allocate overheads into WIP may be used to manipulate the financial statements A 1, 2 and 3 B 2 and 4 only C 1 and 3 only D 2, 3 and 4