| As shown in the illustrated electrically operated watertight door controller, how is the rotation direction of the door motor reversed? |
| A) reversing the direct current direction through the motor series field and the motor armature |
| B) reversing the direct current direction through the motor series field and maintaining the same direct current direction through the motor armature. |
| C) reversing the direct current direction through the motor armature and maintaining the same direct current direction through the motor series field |
| D) reversing the direct current direction through the motor armature and maintaining the same direct current direction through the motor shunt field. |
