The mechanisms of reproductive isolation prevent the reproduction of two individuals from different species. The prezygotic mechanisms disrupt the stages of reproduction before the forming of the zygote or prevent the mating at the start, and the postzygotic mechanisms affect the stages of reproduction after the forming of the zygote.
So, the first and the third example (the urchins and the grasshoppers) show the prezygotic mechanism, as the two individuals are not able to mate or form a zygote.
The second and the fourth example ( zonkey and the death of a zygote) show the working of the postzygotic mechanisms, as the zygote is formed, but it seems to be inviable, and the zonkeys are sterile, preventing the individual to reproduce.
Hey there!
It is mostly like "B". A new area of science promotes experimentation from a different point of view because everything else is explains why the development of the new area of science which could lead to change in a particular theory but they aren't quite the "best" one
SO, that is why
is mostly likely your result
Good luck on your assignment and enjoy your day!
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