**Core Concept**
The patient's presentation of excessive thirst and urination, along with hypernatremia, and laboratory testing revealing pituitary diabetes insipidus, indicates a deficiency in antidiuretic hormone (ADH) production. This deficiency leads to an inability to regulate water reabsorption in the kidneys, resulting in the production of large volumes of dilute urine.

**Why the Correct Answer is Right**
Desmopressin is a synthetic analogue of ADH that is used to treat central diabetes insipidus. It works by binding to vasopressin receptors in the kidneys, stimulating the reabsorption of water and reducing urine production. This action helps to correct the patient's excessive thirst and urination, as well as the associated hypernatremia. Desmopressin is administered via nasal spray or injection and is effective in treating the symptoms of pituitary diabetes insipidus.

**Why Each Wrong Option is Incorrect**
**Option A:** Coicotropin is a synthetic form of adrenocorticotropic hormone (ACTH) and is used to treat adrenal insufficiency, not diabetes insipidus.

**Option C:** hCG (human chorionic gonadotropin) is used in fertility treatments and has no role in the treatment of diabetes insipidus.

**Option D:** Menotropins are a combination of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) and are used in fertility treatments, not in the treatment of diabetes insipidus.

**Clinical Pearl / High-Yield Fact**
In patients with pituitary diabetes insipidus, desmopressin can be administered orally, nasally, or intravenously, but the nasal spray is often the preferred route due to its ease of use and high bioavailability.

**✓ Correct Answer: B. Desmopressin**