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: Radiology
Kerley-B lines are seen when pulmonary venous pressure is: 
Select and explain. 
A. 5 mmHg, B. 10 mmHg, C. 20 mmHg, D. 40 mmHg
C: 20 mmHg
Answer: C: 20 mmHg 
Explanation: Ans. 20 mmHg