The correct option is C Heart valves
In case of defective or damaged heart valves, their closure also becomes improper. This leads to leakage of blood which produces an abnormal sound referred to as heart murmur.
'Bundle of His' is a network of muscle fibres, found in the walls of ventricles and helps in the conduction of the impulses.
The SA node or the pace maker of the heart is a group of specialised nerve fibers where the electrical impulses are generated which help in the contraction of the atria.
Purkinje fibers are specialized for the transmission of excitation and receive conductive signals originating at the atrioventricular node (AVN),