Which of the following is most prone to pulsating discharge flow ?

Answer: Option B

The correct answer is Option B: Reciprocating pump.
Let's break down why:
Pulsating discharge flow means the flow rate isn't constant; it goes up and down in cycles.
Reciprocating pumps use pistons or diaphragms that move back and forth. This creates a distinct "push" of fluid, followed by a "refill" stroke, leading to a strong pulsation.
Centrifugal pumps use a rotating impeller to add energy to the fluid, resulting in a smoother, more continuous flow.
Gear pumps use rotating gears to displace fluid. While there can be some minor pulsations, they are significantly less pronounced than in reciprocating pumps.
Axial flow pumps, similar to centrifugal pumps, use a rotating impeller to move fluid along an axis, resulting in a relatively smooth flow.
In summary, the intermittent pumping action of a reciprocating pump makes it the most likely to produce a pulsating discharge.