Which TWO of the following are arguments that variance analysis from a standard costing system is redundant in a total quality management environment? ( )
选项：

A:

For standard costing to be useful for control purposes, it requires a reasonably stable environment.

B:

The ethos behind a system of standard costing is that performance is satisfactory if it meets predetermined standards

C:

The control aspect of standard costing systems is achieved by making individual managers responsible for the variances relating to their part of the organisation's activities.

D:

Standard costs are set based on ideal standards rather than attainable ones.