What is a primary cause of high blood pressure?

High blood pressure, also known as hypertension, occurs when the force of the blood against the artery walls is consistently too high. This elevated pressure often results from the flow of blood in the arteries being too strong. When blood vessels become narrowed or stiff, the heart has to pump harder to move the blood through the circulatory system, which increases the pressure. This can be influenced by various factors such as genetics, lifestyle choices, and other health conditions.

The other options do not accurately describe causes of high blood pressure. Weak blood flow in an artery would typically result in lower blood pressure, while a reading of 120 over 80 is considered normal blood pressure, not a cause of hypertension. Similarly, the flow of blood likened to a pulse does not directly relate to high blood pressure, as pulse refers to the rhythmic expansion and contraction of arteries with each heartbeat rather than the pressure within those arteries. Thus, the best choice here accurately identifies high blood pressure as caused by an excess flow of blood exerting pressure on artery walls.