I think it is D hope I’m right
Vertebrates developed about 550 million years ago. The oldest vertebrate fossils are those of FISH with no jaws. These e<span>arly jawless fish did not have paired fins and their bodies were covered with heavy, bony scaled, but their skeletons were made of cartilage. For the next 50 million years, they were the only vertebrates.</span>
The correct answer is B. After filtration, the lymph from lymph node travels to the subclavian veins, through efferent lymph vessels. The whole transport process is affected by smooth muscle contraction, changes in pressure and opening/closing of valves.
Answer:
they must focus on it instead of focusing on useless information
