properly designed control activities is recommended to include controls over ...

It is important to relay the message that, properly designed control activities is recommended to include controls over segregation of duties.

For instance, during an audit, if you find out that a supervisor who handles information processing has the ability to authorize payroll changes, you would't put much reliance on that control. 

Related with control risk, a lack of segregation of duties would present control risk as a material misstatement could occur on a timely basis through the course of the entity's operation. 

On a somewhat related topic, components of internal controls would include the control environment, entity's risk assessment process, information systems, control activities to an audit, and monitoring. 

cc: Audit