What is a common cause of low water pressure in a plumbing system?

Low water pressure in a plumbing system can indeed result from multiple factors, which is why the answer encompasses the idea that all listed causes contribute to the problem.

Clogged pipes can accumulate debris, mineral buildup, or other obstructions that restrict water flow. This makes it difficult for water to move freely, leading to reduced pressure throughout the system.

Excessive use of fixtures can create a scenario where the demand for water exceeds the supply being provided, especially during peak usage times. This high demand can lead to lower pressure since the system struggles to deliver sufficient water to all open faucets and fixtures.

When the water supply is shut off, whether intentionally for maintenance or due to other issues, the pressure will obviously drop as water cannot flow through the system until the supply is restored.

Together, these factors illustrate that various conditions can lead to low water pressure, making the choice that encompasses all of these potential causes the correct one.