Answer:
A
Explanation:
Cardiovascular diseases involves the heart.
Any of the above options with regards to blood (etc, white blood cells, red blood cells) are related to circulatory system, not affecting the function of the heart.
Stem cells performing apoptosis to remove old cells is a myth. Stem cells can only differentiate to form cells of the same lineage, not causing other cells to undergo apoptosis. The only external factor that can cause cells to undergo apoptosis is a type lymphocyte in the immune system
Tachycardia is a condition when the heart rate is greater than 100 beats per min at rest. The electrocardiogram is a diagnostic tool that measures and records the electrical activity of the heart. Bradycardia on the other hand is when the heart rate is slower than normal. The Tachycardia and bradycardia can arise from either the SA node or from other areas of the cardiac.