Answer: Option(C)
Step-by-step explanation:
Employee's background check is method to check records of criminal history, financial condition, job history etc of any individual. Employers are permitted to perform this evaluation for verification of that person.
According to the question, conduction of employee's background checking is not the solution in this case because theft has already been done. Background verification should be done before hiring or immediately after hiring so that verified history of person does not hamper the official area.
Other options are correct as they can be used as the measure to maintain the safety of customer's goods.Safe for keeping belongings secure at manager's place, displaying ad regarding unavailability or availability of safe will help the customer to keep their belongings in at secure place or taking accurate step.
The exception is option(C).