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
Transovarian transmission of infection occurs in – a)  Fleasb)  Ticksc)  Mosquitoesd)  Sandfly 
Select and explain. 
A. a, B. c, C. ac, D. bc
D: bc
Answer: D: bc 
Explanation: None