Consider the following statements about the cardiovascular system:
- The sinoatrial (SA) node is the natural pacemaker of the heart.
- Atrial fibrillation is characterized by rapid, irregular heartbeats.
- Angina pectoris is a symptom of myocardial ischemia.
- Hypertension is defined as a blood pressure of 140/90 mmHg or higher.
Which of the following options correctly identifies the true statements?
1
Only 1, 2, and 3 are true
2
Only 2, 3, and 4 are true
3
Only 1, 3, and 4 are true
4
Only 1, 2, and 4 are true
5
Question Not Attempted