I believe it is Wegener's theory did not explain how the continents could move.
The tick uses the dog for two reasons. 1.It uses the dog as a source of food. 2.It also uses a dog for means of transportation from one place too another. And so the dog gains nothing
The answer is A because the heart pumps blood from the heart through pulmonary artery that is low in oxygen and high in carbon dioxide concentration, to the lungs.
