Which of the following factors can contribute to high blood pressure?

High blood pressure, or hypertension, can be influenced by a variety of lifestyle and environmental factors. High stress levels are particularly significant because when a person experiences stress, the body goes through a series of physiological changes. Stress triggers the release of hormones like adrenaline and cortisol, which can cause the heart to beat faster and blood vessels to narrow. This increases the amount of blood pumped through the arteries, thus elevating blood pressure levels.

In addition, ongoing stress may lead to unhealthy behaviors like poor diet, lack of sleep, or increased alcohol consumption, all of which can further contribute to hypertension. Therefore, the relationship between stress and high blood pressure is well established in health research, making it a critical factor to consider.

Other factors such as lack of physical activity can also contribute to high blood pressure, but they do not have the same immediate biochemical impact on the body's response to stress that hormones do. Low salt intake generally is associated with lower blood pressure; hence, it would not contribute to hypertension but rather mitigate it. Hydration is also essential for overall health but is less directly related to the development of high blood pressure compared to stress. Thus, high stress levels stand out as a prominent factor in contributing to high blood pressure.