This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Bronchiectasis, Subject name: Medicine
Which is the most common type of bronchiectasis? 
Select and explain. 
A. Cylindrical, B. Varicose, C. Cystic, D. Irregular
A: Cylindrical
Answer: A: Cylindrical 
Explanation: Most common type of bronchiectasis is the cylindrical type.