The correct answer is: D. Stator.
The stator is the stationary part of an electric motor, while the rotor is the rotating part. The stator is usually made of iron and has a number of windings that are connected to an AC power source. When the power is turned on, the current in the stator windings creates a magnetic field. This magnetic field interacts with the magnetic field of the rotor, causing the rotor to turn.
The starting winding is a type of winding that is used to help the motor start. It is usually connected to a capacitor, which helps to create a stronger magnetic field. This stronger magnetic field makes it easier for the rotor to start turning.
The field winding is the main winding in an electric motor. It is usually connected directly to the AC power source. The field winding creates the magnetic field that causes the rotor to turn.
The armature is the rotating part of an electric motor. It is usually made of copper and has a number of windings that are connected to a commutator. The commutator is a device that switches the current in the armature windings as the rotor turns. This switching of the current creates a magnetic field that interacts with the magnetic field of the stator, causing the rotor to turn.
I hope this explanation is helpful. Please let me know if you have any other questions.