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: Unknown
In a population of 5000, on 1st January, total cases of myopia were 500. Till 31st December, 90 new cases were found. Calculate the incidence of myopia PER 100. 
Select and explain. 
A. 1.8, B. 2, C. 5, D. 18
B: 2
Answer: B: 2 
Explanation: None