This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Respiration, Subject name: Pathology
Alpha-1 antitrypsin deficiency causes 
Select and explain. 
A. Emphysema, B. Bronchitis, C. Bronchieactasis, D. Pneumonia alba
A: Emphysema
Answer: A: Emphysema 
Explanation: Ans. a (Emphysema) . (Ref. Robbins, 6th/709; Harrison medicine 17th ed. 1638)EMPHYSEMA TYPES:1.Centraacinar- Most common type- Most frequently associated with smoking- Most prominent in upper lobe and superior segment of lower lobe2.Panacinar- Alphal antitrypsin deficiency- Prediliction for lower lobe3.Centrilobular-Educational point:# In alphal anti-trypsin deficiency panacinar is common, while in chronic smokers centracinar in commoner.# Garden variety: smoking related to emphysema is usually mixed.