system
Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
Insecticide of choice for sandfly?
assistant
The correct answer is  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.