This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Leprosy, HIV & STDs, Subject name: Social & Preventive Medicine
Most efficient route of HIV transmission is:- 
Select and explain. 
A. Sexual, B. Blood, C. Needles/ syringes, D. Veical
B: Blood
Answer: B: Blood 
Explanation: Routes of transmission of HIV: Sexual - MC Route - 90% new case in India ; least dangerous or least efficient route (0.01-0.1) Blood - Least common Route (<5); Most dangerous / efficient route (90% chances) Needles / syringes - 0.1 - 0.03% chance Veical - 30% (from mother for child