The doctor should check B) The amount of sodium intake the patient takes daily.
Eating salt raises the amount of sodium in your bloodstream and wrecks the delicate balance, reducing the ability of your kidneys to remove the water. The result is a higher blood pressure due to the extra fluid and extra strain on the delicate blood vessels leading to the kidneys. Adding higher blood pressure to an already hbp patient wouldn't have good results.
Hope this helps.