The answer to this question is b carpel that's the answer
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.
Mitrochondira helps the membrane to save inner plasma
True due to the hormones that act upon the kidneys Two examples being Antidiuretic Hormone (ADH) and Aldosterone
ADH increases water permeability of the kidney tubules and Aldosterone decreases the Sodium in the urine and increases the Potassium.