## Core Concept
Bariatric surgery, also known as weight-loss surgery, encompasses various surgical procedures aimed at helping obese individuals lose weight. These procedures often work by restricting the amount of food the stomach can hold, reducing nutrient absorption, or a combination of both.

## Why the Correct Answer is Right
The correct answer includes procedures like **Roux-en-Y gastric bypass**, **Sleeve gastrectomy**, and **Adjustable gastric banding**. These are well-established bariatric surgical procedures.
- **Roux-en-Y gastric bypass** involves creating a small pouch from the stomach and connecting it directly to the small intestine.
- **Sleeve gastrectomy** involves removing a large portion of the stomach, leaving a narrow "sleeve" or tube-like stomach.
- **Adjustable gastric banding** involves placing an adjustable band around the upper portion of the stomach to create a small pouch.

## Why Each Wrong Option is Incorrect
- **Option A:** If it mentions procedures like **Biliopancreatic diversion with duodenal switch**, it's a valid bariatric procedure but might not be listed among the most common ones like gastric bypass or sleeve gastrectomy.
- **Option B:** If it mentions **Gastrostomy**, this is not a bariatric surgical procedure; it's a procedure for directly accessing the stomach for feeding or decompression.
- **Option D:** If it lists **Cholecystectomy** (gallbladder removal) or **Appendectomy** (appendix removal), these are not bariatric surgeries; they are procedures for treating gallstones and appendicitis, respectively.

## Clinical Pearl / High-Yield Fact
A key point to remember is that bariatric surgery is considered for individuals with a **BMI ≥ 40** or those with a **BMI ≥ 35** with significant comorbidities. These surgeries can significantly improve or resolve conditions like type 2 diabetes, hypertension, and obstructive sleep apnea.

## Correct Answer: C.