Answer: Separation of duties
Step-by-step explanation:
From the given case/scenario we can state that Sarah is using the principle of Separation of duties. Separation of duties is referred to as the concept or notion under which one requires more than one individual in order to complete the task. In organizations the separation or segregation is done by accessing more than one individual in a single task in order to prevent error and fraud. This concept or notion is also known as segregation of duties.