This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Anti-Viral Drugs, Subject name: Pharmacology
Dose of oseltamivir for chemoprophylaxis in an infant is:- 
Select and explain. 
A. 3 mg / kg once daily, B. 20 mg once a day, C. 20 mg twice a day, D. 20 mg thrice a day
A: 3 mg / kg once daily
Answer: A: 3 mg / kg once daily 
Explanation: Oral oseltamivir for treatment of influenza Age Weight Dose Frequency Duration <1yr 3mg /kg* Twice daily* 5 days* >1yr <15kg 30mg 15-23kg 45mg 23-40kg 60mg >40kg 75mg* Oral oseltamivir for Chemoprophylaxis 3 months-1yr 3mg /kg* once daily* 7 days* >1yr <15kg 30mg 15-23kg 45mg 23-40kg 60mg >40kg 75mg*