6. Before transferring sperm to the female during mating, the males of some species of beetles use their copulatory organs to re
move the sperm of other males. In cases in which a female mated first with a male of a different species, the male of her own species is particularly adept at removing the other male’s sperm. This is an example of _______ isolation. a. geographical
Mechanical isolation is a type of barrier that prevents the species that are closely related from mating with each other.
It is used in case of plants and animals(here beetles) in which the without compatible sex organs individual of different species will not be able to mate and produce offspring.
In this case constructive interference will occur and it will sum up or add both waves together. So that the resulting wave will travel at speed of 4.2 hertz. So, the correct option is C.