This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Psychiatry
An 18 year old boy came to the Psychiatry OPD with a complaint of feeling changed from inside. He described himself as feeling strange as if he is different from his normal self. He was very tense and anxious yet could not point out the precise change in him. This phenomena is best called as - 
Select and explain. 
A. Delusional mood, B. Depersonalization, C. Autochthonous delusion, D. Over valued idea
B: Depersonalization
Answer: B: Depersonalization 
Explanation: Feeling strange as if different from oneself, i.e. feeling of detached from self is seen in depersonalization disorder.