The correct answer is C) By transferring velocity energy and thermal energy to the turbine blades. In a gas turbine engine, the high-velocity, high-temperature gases from the combustion chamber are directed onto the turbine blades. As the hot gases strike the turbine blades, they transfer their kinetic energy (velocity) and thermal energy to the blades, causing the turbine rotor to rotate. This rotational motion is then used to drive the compressor, which supplies compressed air to the combustion chamber, as well as other components of the engine. The other answer choices are incorrect because: A) creating a low-pressure area does not directly cause the rotor to rotate, B) converting the high-velocity gas to low-velocity gas does not explain the transfer of energy to the turbine blades, and D) increasing the velocity of the gases alone does not explain how the rotor is set in motion.