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
RDA of Retinol during pregnancy 
Select and explain. 
A. 500 mcg, B. 600 mcg, C. 700 mcg, D. 800 mcg
D: 800 mcg
Answer: D: 800 mcg 
Explanation: None