All of the following are necessary for budgets to be effective except : a. Goals should be challenging but attainable. b. Managers should be aware of potential negative outcomes of budgeting, such as budgetary slack. c. Evaluations should be made carefully with opportunities to explain differences between actual and budgeted amounts. d. All levels of management from all departments with an organization should be involved in the budgeting process. e. Employees who will have performance evaluated according to the budget standards should not be involved in preparing the budget..