ANS:B - turbulent

Maximum heat transfer rate is typically obtained in turbulent flow. Explanation:

• Turbulent flow is characterized by chaotic and irregular movement of fluid particles. This chaotic motion promotes better mixing and enhances heat transfer.
• In laminar flow, fluid particles move in parallel layers with little to no mixing, which limits heat transfer.
• Creeping flow occurs at very low velocities and is characterized by smooth, orderly motion of fluid particles. Heat transfer in creeping flow is typically low due to the lack of mixing.
• The transition region is where flow characteristics transition between laminar and turbulent regimes. While some enhancement in heat transfer may occur in the transition region compared to laminar flow, it generally does not match the heat transfer rates achieved in fully turbulent flow.