Abnormal vascular regulation by endothelial cells in small vessels of the heart contributes to:. a. Hypertension b. Dysrhythmias c. Truncus arteriosus d. Ischemic heart disease

The correct answer to the question is option D

ISCHEMIC HEART DISEASE.

Explanation: To answer the question effectively, let us look at the options given,what they are and how they affect the heart.

Endothelial cells play a crucial role in the regulating vascular tone,They do so by secreting variable amounts of constricting and relaxing factors inorder to control tissue perfusion.

Hypertension on the other hand occurs as a result of factors that varies distinctively and not all related to vascular tone.

Dysrhythmias on it's own will affect the function and conduction of heart chambers but not necessarily vascular tones.

Truncus arteriosus results in only in one large artery exiting/leaving the heart.