**Core Concept**
Obesity is a complex condition characterized by an excess of body fat, which can lead to various metabolic, cardiovascular, and musculoskeletal complications. The pathophysiology of obesity involves dysregulation of energy balance, insulin resistance, and inflammation, ultimately contributing to multiple comorbidities.

**Why the Correct Answer is Right**
Obesity is associated with several complications, including type 2 diabetes mellitus, cardiovascular disease, hypertension, dyslipidemia, and certain types of cancer. The underlying mechanisms involve insulin resistance, hyperglycemia, and inflammation, which contribute to the development of these comorbidities. The increased risk of cardiovascular disease in obese individuals is attributed to the development of hypertension, dyslipidemia, and endothelial dysfunction.

**Why Each Wrong Option is Incorrect**
* **Option A:** Not mentioned in the context of obesity complications.
* **Option B:** While sleep apnea is a complication of obesity, it is not the only one.
* **Option C:** Not a direct complication of obesity; however, it may be associated with the metabolic syndrome.

**Clinical Pearl / High-Yield Fact**
Obesity is a major risk factor for the development of type 2 diabetes mellitus, and the risk increases exponentially with increasing BMI. A BMI of 30-34.9 is associated with a 2-3 fold increased risk, while a BMI ≥ 35 is associated with a 5-6 fold increased risk.

**Correct Answer:** B. Sleep apnea.