Problem: A 28-year-old woman presents with polyuria, polydipsia, and fatigue. Her lab results show hypernatremia and low urine osmolality. The water deprivation test is done, and there is no change in urine osmolality after desmopressin (ADH) administration. Which of the following is the most likely diagnosis? Need Assignment Help? Central diabetes insipidus Nephrogenic diabetes insipidus Psychogenic polydipsia Syndrome of inappropriate antidiuretic hormone secretion (SIADH)