Which system includes a hand pump and a new supply line from the bottom of the reservoir to the hand pump?

• A. System A
• B. System B
• C. System C
• D. System D

Answer: (D)

The main idea here is recognizing a manual priming or backup feed arrangement in a fluid system. A hand pump paired with a supply line that comes from the bottom of the reservoir to the pump is a telltale setup for priming the system manually when the primary (electric) pump isn’t available or isn’t delivering pressure.

Why this is the best fit: drawing from the bottom of the reservoir ensures the pump can suction fluid and avoid drawing air or vapor, which helps create a prime quickly. The hand pump provides a user-driven means to pressurize or push fluid through the line so the system can operate or be bled of air even without power. This configuration is specifically about enabling manual control and priming, not about normal automatic pumping.

Other systems would typically rely on an electric or turbo-driven pump with a different suction arrangement and wouldn’t require a hand pump or a bottom-feed line designed for priming. The presence of both a hand pump and a bottom-suction line signals a deliberate manual priming capability rather than standard automatic operation.