Ned Seeks Therapy After Having Recurrent Episodes of Feeling "Detached

Ned seeks therapy after having recurrent episodes of feeling "detached from himself" for several months,but he has not lost his self-awareness or memory.He notes that he feels like a robot,disconnected from his movements and actions.He is most likely suffering from ______.

A) dissociative fugue
B) conversion disorder
C) dissociative identity disorder
D) depersonalization disorder