**Core Concept**
Congenital hydrocele is a condition where fluid accumulates in the scrotum due to a patent processus vaginalis, which is a communication between the abdominal cavity and the scrotum. The treatment aims to close this communication and prevent further fluid accumulation.

**Why the Correct Answer is Right**
The correct approach to treating congenital hydrocele is surgical exploration and ligation of the patent processus vaginalis. This procedure involves making an incision in the scrotum and identifying the communication between the abdominal cavity and the scrotum. By ligating (tying off) the patent processus vaginalis, the communication is closed, and fluid accumulation is prevented. This procedure is typically performed in infants and young children.

**Why Each Wrong Option is Incorrect**
**Option A:** Sclerotherapy is not a suitable treatment for congenital hydrocele as it involves injecting a sclerosing agent into the hydrocele sac, which is not effective in closing the patent processus vaginalis.
**Option B:** Conservative management with watchful waiting is not appropriate for congenital hydrocele as it may lead to complications such as testicular torsion or incarceration.
**Option C:** Aspiration of the hydrocele fluid is not a definitive treatment as the fluid will continue to accumulate through the patent processus vaginalis.

**Clinical Pearl / High-Yield Fact**
It's essential to diagnose and treat congenital hydrocele promptly to prevent complications and ensure proper testicular development.

**Correct Answer:** C. Surgical exploration and ligation of the patent processus vaginalis.