Final answer:
According to JNC7 guidelines, the patient's blood pressure of 128/89 mm Hg would be classified as prehypertensive.
Step-by-step explanation:
The patient's blood pressure of 128/89 mm Hg falls within the prehypertension category according to JNC7 guidelines. Hypertension is defined as blood pressure measurements of 140/90 mm Hg or higher, while prehypertension is defined as pressures between 120/80 and 140/90 mm Hg. Therefore, the correct classification for this patient's blood pressure would be d. Prehypertensive.