Question：What are the disadvantages of flexible budgets?
　　A. They are not very useful for decision making.
　　B. They are more time consuming to prepare than fixed budgets.
　　C. They fail to provide an appropriate yardstick for cost control purposes.
　　D. They are based on a set of assumptions which may be over simplistic.
　　The correct answers are:They are more time consuming to prepare than fixed budgets; They are based on a set of assumptions which may be over simplistic.
　　解析：Managers may not have the time available to prepare flexible budgets to cover all possible scenarios. Therefore they will often make simplifying assumptions.
　　They are useful for decision making as they are flexed to the actual level of activity, and therefore allow actual costs to be compared against the standard costs for that actual activity.