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
Insecticide of choice for sandfly? 
Select and explain. 
A. DDT, B. Malathione, C. Paris green, D. None
A: DDT
Answer: A: DDT 
Explanation: Ans. is 'a' i.e., DDT Resistance to DDT has not been demonstrated in sandflies A single application of DDT or lindane has been found effective in reducing sandflies. 7 DDT residue may remain effective for a period of 1 to 2 years and lindane only for a period of 3 months.