I'm pretty sure the answer is A.
The keyword here is "area per volume" which is available in both cases. Besides capillaries are smaller than arteries they have in total more area as there are many vessels of then. The More the area/volum, the less the velocity
Answer:
These include temporal isolation, ecological isolation, behavioral isolation, and mechanical isolation. Post-zygotic barriers: barriers that come into play after two species have mated. These include genetic incompatibility, zygotic mortality, hybrid inviability, hybrid sterility, and hybrid breakdown.
Explanation:
