Answer:Major depressive disorder--- D
Step-by-step explanation: Major depressive disorder is a common clinical depression disorder that affect how an individual thinks, feels and performs his or her daily activities in all areas of their lives due to accumulation of different thoughts in their head leading to distortion in mood and behavior affecting their sleeping pattern and can cause loss of appetite.
George, a 22-year-old mechanic, who always seems to have seem to have such sleeping and appetite problems combined with accumulation of thoughts in his head should see help and would likely be diagnosed with MDD, Major Depressive Disorder.