Pump Definition
A pump is a mechanical device that is used to transfer fluids (liquids or gases) from one place to another. It applies mechanical force to the fluid, which increases its pressure and allows it to flow through pipes or other conduits.

Pump Types
There are various types of pumps available, including centrifugal pumps, reciprocating pumps, and axial flow pumps. Each type has its own specific design and application, but they all follow the same basic principle of converting mechanical energy into hydraulic energy.

Pump Operation
When a pump is in operation, it uses mechanical energy to create a pressure difference within the fluid. This pressure difference causes the fluid to move from an area of high pressure to an area of low pressure. The pump provides the mechanical force required to overcome the resistance of the fluid and move it through the system.

Pump Conversion
In the given options, the correct answer is option 'B', which states that a pump converts mechanical energy into hydraulic energy. This is because the mechanical energy provided by the pump's motor or engine is used to increase the pressure of the fluid, thereby converting it into hydraulic energy.

Explanation of Other Options
- Option 'A' is incorrect because a pump does not convert hydraulic energy into mechanical energy. Instead, it uses mechanical energy to create hydraulic energy.
- Option 'C' is incorrect because a pump does not convert kinetic energy into mechanical energy. Kinetic energy is the energy of motion, whereas mechanical energy refers to the energy associated with the movement or position of an object.
- Option 'D' is incorrect because all the other options are incorrect. A pump does convert energy, but it specifically converts mechanical energy into hydraulic energy.

Conclusion
In conclusion, a pump is a device that converts mechanical energy into hydraulic energy. It achieves this by using mechanical force to increase the pressure of a fluid, allowing it to flow from one place to another.