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: Ophthalmology
A 28-week baby suffered from respiratory distress syndrome at bih. On day 14 of life, he developed sepsis. No other co-morbidity was seen. He should be evaluated for retinopathy of prematurity at what postnatal age? 
Select and explain. 
A. 2 weeks, B. 4 weeks, C. 6 weeks, D. 8 weeks
B: 4 weeks
Answer: B: 4 weeks 
Explanation: Ans. b. 4 weeks