The correct answer is C.
OBJ-5.2: If the fan in the power supply is faulty, replace the entire power supply. You should never attempt to repair or fix a broken power supply or broken power supply cooling fan due to the power supply’s high voltage electrical components. When a fan creates a grinding sounds, this is evidence of an impending failure and the device needs to be replaced. Techicians should never open a power supply or replace any of its internal components, therefore the entire power supply should be replaced in this scenario.