"AV node" receives the depolarization wave from the atria and passes impulses onto the ventricles.
Explanation:
The atrioventricular node or AV node is a portion of the electrical conduction system of the heart that organizes the top of the heart. It electrically attaches the atria and ventricles. The AV node is a bunch of cells in the middle of the heart among the atria and ventricles, and performances like a gate that decelerates the electrical signal before it enters the ventricles. This postponement gives the atria time to contract before the ventricles do.
I am not 100% sure but I believe it's A. a deck of cards based on my logic. A baseball and a coffe mug is too big and an open palm can vary in size too much.
