Answer
d.
Work Step by Step
Option a. is incorrect. The ventricles are the bottom chambers of the heart.
Option b. is incorrect. The septa divide the atria from the ventricles and each atrium and ventricle from the other.
Option c. is incorrect. Myocardia is the technical name for heart muscle.
Option d. is correct. The atria are the upper chambers of the heart. The right atrium receives deoxygenated blood from the body that subsequently is pumped to the lungs by the right ventricle. The left atrium receives oxygenated blood from the lungs to be pumped to the rest of the body by the left ventricle.
