A 42-year-old man with bipolar disorder presents with persistent polyuria and polydipsia. Vital signs show BP 128/82 mmHg, HR 88 bpm, RR 16/min, temp 37°C. Labs reveal serum sodium 149 mEq/L, serum osmolality 310 mOsm/kg, and urine osmolality 180 mOsm/kg despite dehydration. Water deprivation test fails to concentrate urine, and desmopressin administration produces no significant response. Serum glucose is normal. He takes lithium carbonate daily for mood stabilization. Which medication is the most likely cause of his condition?

1. A)Lithium induced renal resistance to ADHGABARITO
2. B)Pituitary stalk transection
3. C)Adrenal insufficiency
4. D)Psychogenic polydipsia
5. E)Excess ADH secretion from small cell lung carcinoma