This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Basics of Psychiatry, Subject name: Psychiatry
Which of the following is thought disorder? 
Select and explain. 
A. Circumstantiality, B. Tangentiality, C. Prolixity, D. All of the above
D: All of the above
Answer: D: All of the above 
Explanation: Prolixity is a milder form of "flight of ideas". As mentioned in the text, flight of ideas can be considered as both a disorder of stream of thought and form of thought.