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
Freshly prepared ORS should be used within 
Select and explain. 
A. 12 hours, B. 1 day, C. 2 days, D. 4 hours
B: 1 day
Answer: B: 1 day 
Explanation: None