Answer B is most accurate, due to variation in large populations of insects. The few ants that may be able to survive the spray will reproduce to make the next generation. Answer A denies variation in the population. Answer C is reflective of a very common error that individual insects develop resistance to chemicals when the chemicals are applied. It would be worth mentioning to students that typically this type of resistance takes a long time to become a problem, but this explains why current human head lice treatments that were very effective several years ago are no longer working well in some areas.
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