Answer :
A Septum separates the heart's left and right sides to keep oxygenated and deoxygenated blood from mixing.
What is a septum?
The septum of the heart is the wall that divides the left side of the heart to the right side.
The septum that divides the upper chambers of the heart is called the atrial septum.
The ventricular septum divides the lower chambers of the heart.
Thus., the correct option is b.) It separates the heart's left and right sides to keep oxygenated and deoxygenated blood from mixing.
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