Concerning the baffles of a shell-and-tube heat exchanger, what statement is true?

Correct Answer: Option C — The baffles are used to support the tubes, guide flow, and increase the velocity of the fluid flowing through the shell.

Baffles serve a dual purpose: they provide structural support to prevent tube vibration and force the shell-side fluid to follow a tortuous path. This redirection increases fluid velocity and turbulence across the tube bundle, significantly improving the overall heat transfer coefficient compared to a straight-through shell flow.