The sequence of an impulse moving through the conduction system of the heart is
A) sinoatrial node,atrioventricular node,Purkinje fibers,bundles of His
B) atrioventricular node,Purkinje fibers,bundles of His,sinoatrial node
C) sinoatrial node,atrioventricular node,bundles of His,Purkinje fibers
D) sinoatrial node,bundles of His,atrioventricular node,Purkinje fibers