Final answer:
Atrial hypertrophy can indeed cause an enlarged P wave on an electrocardiogram, as it indicates an increase in atrial muscle mass leading to a larger electrical signal during depolarization.
Step-by-step explanation:
The statement that atrial hypertrophy would probably cause an enlarged P wave on an electrocardiogram is true. The P wave on an ECG represents the depolarization of the atria which precedes atrial contraction. When the atrial muscle is enlarged, as in atrial hypertrophy, the depolarization process takes longer and results in a larger electrical signal which manifests as an enlarged or amplified P wave on the ECG. This change in the P wave can be indicative of an increase in atrial muscle mass and, therefore, suggests that the atria are working harder than normal to pump blood.