A Vascular Sinus, Such as the Coronary Sinus, Is Best

Multiple Choice

A vascular sinus, such as the coronary sinus, is best described as:

A) a thin-walled vein that has no smooth muscle to alter its diameter.
B) a thin-walled artery that has no smooth muscle to alter its diameter.
C) a connection between blood vessels that allows for multiple routes of blood flow.
D) a blood-filled connective tissue.