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: Pathology
Which of the following is a major complication of chronic bronchitis? 
Select and explain. 
A. Myxedema, B. Pneumothorax, C. Emphysema, D. Malignant transformation
D: Malignant transformation
Answer: D: Malignant transformation 
Explanation: Chronic bronchitis predisposes those affected to squamous neoplasia of the bronchial epithelium (i.e., bronchogenic carcinoma).