Answer: b. False
Step-by-step explanation:
The long refractory period of cardiac muscle does not prevent tetanic contractions of the heart. Tetanic contractions refer to sustained, continuous contractions without relaxation. While the refractory period of cardiac muscle helps prevent the occurrence of tetanic contractions under normal conditions, there are certain abnormal conditions or arrhythmias in which the heart can experience sustained contractions. These abnormal contractions can disrupt the heart's pumping function and lead to complications.