At Change of Shift,two Nurses (One from Each Shift)discover a Discrepancy

At change of shift,two nurses (one from each shift) discover a discrepancy in the narcotics inventory for morphine 5 mg/mL vials.The count is short by one vial.Which of the following steps should be taken to reconcile the count? (Select all that apply. )

A) All nurses having access to the Pyxis machine or the narcotics cabinet should be asked about medication they have given.
B) Steps must be retraced to identify whether someone forgot to record any medication removed.
C) Check patient charts (MAR) to see if medication was given that was not signed for on the inventory report.
D) Notify the nursing supervisor (charge nurse) and the pharmacy department of any undocumented (unreconciled) discrepancy.
E) None of above