The correct answer is B) To convert velocity to pressure. In an axial gas turbine compressor, the stator's primary function is to convert the high-velocity air flow from the rotor blades into increased pressure. The stator vanes are stationary and redirect the high-velocity air from the rotor, causing a decrease in velocity and a corresponding increase in pressure. This pressure increase is necessary to feed the combustion section of the gas turbine engine. The other options are incorrect as they do not accurately describe the stator's role in an axial gas turbine compressor.