What is required for a sump pump that discharges drainage that cannot rely on gravity?

The correct choice requires a check valve and a full open valve to effectively manage the discharge from a sump pump that cannot rely on gravity for drainage.

A check valve is essential in this setup because it prevents backflow of water into the sump pit when the pump is not operating or when there are fluctuations in the pressure. This ensures the sump pump can efficiently discharge water without getting overwhelmed by backflow, maintaining its operational integrity.

The full open valve allows for unrestricted flow of water from the sump pump to the discharge point. This is crucial in scenarios where gravity cannot assist, as it ensures that the water being pumped is expelled quickly and efficiently without creating additional pressure buildup or hinderance in the system.

Considering the other choices, while alternative components like a battery backup and power supply, float switch, pressure gauge, or manual override may be beneficial in certain contexts, they do not directly address the primary requirement for ensuring effective drainage in a sump pump system that relies on mechanical means rather than gravity.