Which statement describes open-ended delayed surface marker buoys?

Open-ended delayed surface marker buoys are designed in such a way that their bottom is open, allowing gas to escape. This feature is essential as it enables the buoy to be buoyant and maintain an appropriate position during its ascent to the surface. The open bottom facilitates the release of gas that may accumulate during deployment, ensuring that air can freely vent as the buoy rises through the water column. This design is particularly beneficial for divers signaling their position or marking locations during a dive, as it prevents the buoy from becoming overly buoyant or being pulled under before it reaches the surface.

The design of the buoy, with an open bottom, is intentional to manage the buoy's behavior in the water, making this option accurate. Other statements regarding the buoy being sealed or having a closed bottom do not apply to this type of equipment, which would inhibit proper function or diver safety.