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: Social & Preventive Medicine
In a given population of 1000, new cases of lung cancer is 50, old cases in the same population are 100. What is the prevalence 
Select and explain. 
A. 1.50%, B. 15%, C. 150, D. 13%
B: 15%
Answer: B: 15% 
Explanation: None