9.22歲男性大學生近半年來覺得口渴、多尿，1天喝冷飲約5公升，體重增加近10 Kg，來診身體檢查無特別發現，BP 126/82 mmHg、PR 80/min regular，抽血檢查 Na 140 mM/L、K 3.5 mM/L、Urinalysis protein ( - )，sugar ( - )，您覺得下列檢查何者為診斷所必要︰ (1)Water deprivation test (2)dDAVP test (3)plasma Osm. (4)HbA1C (5)MRI of sella
(A)(1)+(2)+(3)
(B)(2)+(3)+(4)
(C)(3)+(4)+(5)
(D)(1)+(4)+(5)
(E)(1)+(2)+(5)