the chemical deltamethrin (dm) is another insecticide that is used to kill mosquitoes. not surprisingly, mosquito populations sprayed with dm for several years evolve to become resistant. however, if dm spraying is stopped for a few years, the population will lose its resistance. what is the most likely description of how this occurs? group of answer choices mosquitoes do not need to be resistant to dm when it is not present. the immune systems of mosquitoes not exposed to dm gradually lose their ability to cope with dm. when dm is not present, mosquitoes that are resistant to dm do not survive as well as mosquitoes that are not resistant to dm. this was purely a random event.