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
Which is most dangerous for transmitting plague- 
Select and explain. 
A. Blocked flea, B. Partial blocked flea, C. Both, D. Unblocked flea
B: Partial blocked flea
Answer: B: Partial blocked flea 
Explanation: None