Final answer:
The nurse should document a chart entry with all relevant information including the type of order, medication details, and confirmation of the order, which in this case is option A: 'VO Dr. Day/J. Winds, RN, read back'.
Step-by-step explanation:
The correct chart entry that the nurse should document after obtaining a telephone order for morphine for a patient in pain would be option A: 12/16/20XX 0915 Morphine, 2 mg, IV every 4 hours for incisional pain. VO Dr. Day/J. Winds, RN, read back.
This documentation specifies the date and time, medication ordered, dosage, route, frequency, and purpose, as well as the type of order (Verbal Order or VO), the physician's name, and the nurse who took the order and performed the read-back confirmation, which is a safety measure to ensure accuracy of orders received verbally.