**Core Concept**
Nocturnal enuresis, also known as bedwetting, is a common condition in children where they involuntarily urinate during sleep. The underlying principle in treating nocturnal enuresis involves addressing the underlying causes, such as nocturnal polyuria, bladder instability, or sleep disorders, to prevent nocturnal urine production and promote bladder control.

**Why the Correct Answer is Right**
The first-line treatment for nocturnal enuresis often involves the use of desmopressin, a synthetic analogue of vasopressin that reduces nocturnal urine production. Desmopressin acts by stimulating the V2 receptors in the renal collecting ducts, leading to a decrease in water reabsorption and a decrease in nocturnal urine production. This reduces the likelihood of nocturnal enuresis. Additionally, behavioral therapies such as bladder training, alarm therapy, and motivational therapy can also be effective in treating nocturnal enuresis.

**Why Each Wrong Option is Incorrect**
**Option A:** This option may involve a medication that is not typically used as a first-line treatment for nocturnal enuresis, such as a diuretic, which would increase urine production and worsen the condition.
**Option B:** This option may involve a behavioral therapy that is not effective in treating nocturnal enuresis, such as a therapy that focuses solely on addressing sleep disorders without addressing bladder control.
**Option C:** This option may involve a surgical intervention that is not typically used to treat nocturnal enuresis, such as a procedure to implant a bladder stimulator.

**Clinical Pearl / High-Yield Fact**
A key aspect of treating nocturnal enuresis is to address the underlying causes, such as nocturnal polyuria or bladder instability, and to use a combination of pharmacological and behavioral therapies to promote bladder control and prevent nocturnal urine production.

**Correct Answer:** D