Which of the Following Is True in the Context of Characteristics

Which of the following is true in the context of characteristics of effective controls?

A) For effective controls, the cost of using the controls should be more than the benefit derived from using them.
B) Supervisors and employees want controls that unduly infringe on their privacy.
C) An effective control system is one that helps the supervisor direct his or her efforts toward spotting significant problems.
D) Normally, a supervisor is not expected to use the control system higher-level managers have established.