Ans. is 'a' i.e., Use of alkaline detergent As the name suggests, nondeliberate antimosquito effect means mosquito control measure which is not intentional or deliberate. Mosquitoes do not grow in water with alkali. Since most soaps and detergents are alkali based, use of soaps and detergents has a nondeliberate antimosquito effect (because soaps and detergents are not intended to use as mosquito control measure). o Other methods, which are intended to be used as mosquito control measures are deliberate mosquito control measures. Deliberate mosquito control measures Anti-larval measures Anti-adult measures Protection against mosquito bites (a) Environmental control (a) Residual sprays (a) Mosquito net (b) Chemical control (b) Space sprays (b) Screening (c) Biological control (c) Genetic control (c) Repellents