Which of the following can lead to elevated intracranial pressure?

Hydrocephalus is a condition characterized by an accumulation of cerebrospinal fluid (CSF) in the ventricles of the brain, which can lead to increased intracranial pressure (ICP). The buildup of CSF occurs due to an imbalance in its production and absorption, often resulting from blockages in the ventricular system or other abnormalities. As the fluid accumulates, it exerts pressure on the brain tissue and can lead to various neurological symptoms and complications.

Elevated ICP can have serious consequences, including the risk of brain herniation, which can be life-threatening. Therefore, hydrocephalus is a well-recognized cause of increased ICP, making it the correct answer in this context.

In contrast, while increased heart rate, lack of sleep, and dehydration may influence overall health, they do not directly cause an increase in intracranial pressure in the same manner that hydrocephalus does. Increased heart rate can be a response to various physiological stresses or conditions, lack of sleep can impact brain function, and dehydration can lead to various complications, but these factors do not lead to the pathological accumulation of fluid that accounts for the rise in ICP seen in hydrocephalus.