Which of the following is a water-saving measure commonly used in buildings?

• A. Rainwater harvesting.
• B. Double-glazed windows.
• C. Low-flow fixtures.
• D. Solar PV panels.

Answer: (C)

Focusing on reducing water use at the point of use, low-flow fixtures limit how much water is delivered by taps, toilets, and showerheads. They achieve savings through flow restrictors, aerators, and efficient valve designs, which cut water use while keeping user experience acceptable. Because these devices are inexpensive to install and work in everyday scenarios, they’re widely adopted in both new buildings and renovations, making them a common and practical water-saving measure.

Rainwater harvesting also saves water, but it requires additional infrastructure and maintenance, so it isn’t as universally installed. Double-glazed windows mainly cut energy losses, not water use, and solar PV panels generate electricity rather than directly reducing water consumption.