## Core Concept
Laparoscopy involves insufflating the abdominal cavity with a gas to create a clear visual and operative field. The choice of gas is crucial for safety and efficacy.

## Why the Correct Answer is Right
The correct answer, **CO2 (Carbon Dioxide)**, is the preferred gas for laparoscopy due to its favorable properties. It does not support combustion, which reduces the risk of fire during procedures involving electrosurgery. CO2 is also highly soluble in blood, which minimizes the risk of gas embolism. Its rapid absorption from the peritoneal cavity helps in quick recovery and reduces postoperative discomfort.

## Why Each Wrong Option is Incorrect
- **Option A: O2 (Oxygen)** - Supports combustion and could increase the risk of fire during electrosurgical procedures. It's not used for insufflation.
- **Option B: N2 (Nitrogen)** - Although it's a major component of air, nitrogen is not used for laparoscopy because it's not absorbed well from the peritoneal cavity, and it supports combustion.
- **Option D: Helium** - While helium is an inert gas and does not support combustion, it is not absorbed well by the body. This can lead to postoperative discomfort and a higher risk of gas embolism compared to CO2.

## Clinical Pearl / High-Yield Fact
A key point to remember is that **CO2** is used for laparoscopy because of its **high blood solubility**, which reduces the risk of complications like gas embolism. Also, remember that CO2 is **rapidly absorbed**, aiding in quicker recovery.

## Correct Answer: C. CO2.