Question 292Motor Plants - Assistant Engineer

The correct answer is C) spindle nut. The spindle nut, labeled as item "O" in the illustration, is responsible for securing the impeller in place within the device. This is a critical component that ensures the proper and safe operation of the equipment. The other answer choices are incorrect because: A) A fair flow nut is not a component typically found in this type of device. B) The inlet directional guide is a separate component, likely labeled with a different letter. D) The impeller locking device is a different mechanism used to secure the impeller, distinct from the spindle nut.