Conduction of the electrical signal slows down as it passes through the
a. av bundle
b. fibers of the av node
c. internodal pathways
d. bundle branches
e. purkinje fibers

The correct answer is option C- internodal pathways.

Explanation:

The electrical conduction signals are generated from the SA node (sino-atrial node) in the right atrium which travels to the AV node (atrioventricular node) in the inferior portion of the right atrium through the internodal pathway.

The impulse spread in the atria through myocardial cells which contract in response to impulse within one-third of a second. After contraction the impulse transmission slows down or delays through the internodal pathway to give enough time to pump blood to ventricles.

Thus, option C- internodal pathways is the correct option.