**Core Concept**
Percutaneous nephrolithotomy (PCNL) is a minimally invasive surgical procedure used to remove large kidney stones, especially those greater than 2 cm in size, from the renal pelvis or calyces. This approach is preferred for stones that are difficult to access or are too large for extracorporeal shock wave lithotripsy (ESWL).

**Why the Correct Answer is Right**
The patient has a 3 cm left renal pelvic stone with no distal obstruction, which makes it an ideal candidate for PCNL. This procedure involves inserting a small scope through the skin and into the kidney to remove the stone. PCNL is particularly effective for stones located in the renal pelvis or calyces, which is the case here. The procedure allows for the removal of the stone in a single session, reducing the risk of complications and the need for multiple procedures.

**Why Each Wrong Option is Incorrect**
**Option A:** Extra-corporeal shock wave lithotripsy (ESWL) is not the ideal option for this patient because ESWL is more effective for smaller stones (less than 2 cm) and may require multiple sessions.

**Option B:** Laparoscopic nephrolithotomy is a minimally invasive surgical approach, but it is more complex and may not be suitable for stones located in the renal pelvis or calyces.

**Option D:** Medical dissolution therapy with oral potassium citrate is not effective for large stones like the one in this patient, and it may take months to years to achieve significant stone dissolution.

**Clinical Pearl / High-Yield Fact**
When considering PCNL, it's essential to assess the stone burden and location, as well as the patient's overall health and renal function. A high success rate and reduced risk of complications make PCNL a preferred option for large kidney stones.

**Correct Answer Line**
✓ Correct Answer: A. Percutaneous nephrolithotomy (PCNL)