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Question
What causes the semilunar valves to close?
A. higher pressure in the ventricles than in the atria
B. higher pressure in the aorta and pulmonary trunk than in the ventricles
C. higher pressure in the atria than in the ventricles
D. higher pressure in the ventricles than aorta and pulmonary trunk
Answer
This answer is hidden. It contains 1 characters.
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