Question
a arrogate opositiony
14. A large population of houseflies was sprayed with a newly developed, fast-acting
insecticide. The appearance of some houseflies that are resistant to this insecticide
supports the concept that
(1) species traits tend to remain constant
(2) biocides cause mutations
(3) variation exists within a species
(4) the environment does not change
Answer
(3) Variation exists within a species.