This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Medicine
In an obese patient the most likely respiratory change is 
Select and explain. 
A. FRC is unchanged, B. Alveolar hypo ventilation, C. Residual volume is decreased, D. Normal work of breathing
B: Alveolar hypo ventilation
Answer: B: Alveolar hypo ventilation 
Explanation: Obesity hypoventilation syndrome is characterized by :

Obesity.
Hypoxemia.
Hyper carbia.
Respiratory acidosis.
Pulmonary hypertension.
Right ventricular failure.