Which of the Following Does Not Characterize the Circulatory Systems

Multiple Choice

Which of the following does not characterize the circulatory systems of birds and mammals?

A) There are more blood vessels in the systemic circuit than in the pulmonary circuit.
B) The pulmonary and systemic circuits are entirely separate.
C) Higher pressures are required in the pulmonary circuit relative to the systemic circuit.
D) There is no mixing of blood high in oxygen with blood low in oxygen.
E) The systemic circuit always receives blood with the highest oxygen content.