A Physiologist Is Trying to Study the Cardiac Action Potential

A physiologist is trying to study the cardiac action potential. He takes the reading from 4 different points within normal cardiac tissue. The results, expressed in terms of speed of conduction (meters per second) , are as follows:Point 1 - 0.05 m/sec Point 2 - 0.3 m/sec
Point 3 - 1.1 m/sec
Point 4 - 2.2 m/secFrom the following list of locations, which most likely corresponds to the order of points 1-2-3-4 (AV = atrioventricular) ?

A) Atrial muscle, ventricular muscle, Purkinje system, AV node
B) AV node, Purkinje system, ventricular muscle, atrial muscle
C) AV node, ventricular muscle, atrial muscle, Purkinje system
D) Purkinje system, AV node, ventricular muscle, atrial muscle
E) Ventricular muscle, AV node, Purkinje system, atrial muscle