The correct answer is option C: Maximum.

Explanation:
- Velocity is a measure of how quickly a fluid-particle is moving in a given direction. In a pipe, the fluid-particles near the walls of the pipe experience frictional drag, which slows them down, while the fluid-particles in the center of the pipe have less contact with the walls and experience less drag.
- Due to this lower drag, the fluid-particles at the center of the pipe section can move faster compared to the particles near the walls.
- As a result, the velocity of the fluid-particle at the center of the pipe section is maximum compared to the particles near the walls.
- This is known as the "velocity profile" of the fluid flow in a pipe, where the velocity is highest at the center and gradually decreases towards the walls.
- The shape of the velocity profile depends on the flow conditions and the type of flow (laminar or turbulent).
- In laminar flow, the velocity profile is parabolic, with the maximum velocity occurring at the center of the pipe section.
- In turbulent flow, the velocity profile is flatter and broader compared to laminar flow, but the maximum velocity still occurs at the center of the pipe section.
- The concept of the maximum velocity at the center of the pipe section is important in various applications, such as designing efficient pipe systems, calculating pressure drops, and understanding fluid flow behavior.
- Therefore, the correct answer is option C: Maximum.