A Marketing Researcher Reviews the Month's Sales Slips for a Convenience

A marketing researcher reviews the month's sales slips for a convenience store, and compares them with restocking orders, in order to determine which products are being stolen from the shelves. This study has little control. Why is this the case?

A) The researcher has no control over whether people choose to shoplift.
B) It does not control for extraneous variables.
C) No variables are manipulated.
D) The design is descriptive or correlational; as compared with other types of research, control is low.
E) The data collected were actually generated by other people and may be erroneous.