Final answer:
The best action for preventing medication errors is to review the patient's previous hospital records and encourage patient attentiveness to their medications.
Step-by-step explanation:
The best action to assist nurses in the prevention of medication errors for Ms. Granger, a 49-year-old who is newly admitted to the hospital, would be to review the patient's previous hospital records. This method allows healthcare professionals to cross-reference her current medication orders with her history to ensure accuracy and continuity of care. Additionally, encouraging Ms. Granger to be attentive and to question any discrepancies with her medications fosters a culture of safety and patient involvement in care.