Which of the following strategies is most effective in enhancing heat transfer in a heat exchanger by reducing resistance?

A、Increasing the flow rate of the working fluid to enhance turbulence and reduce boundary layer thickness.
B、Using a larger surface area for heat exchange without changing the fluid properties.
C、Increasing the temperature difference between the hot and cold fluids while maintaining the same flow rates.
D、Insulating the heat exchanger to minimize heat losses to the environment.