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
A person who laughs one minute and cries other minute has: 
Select and explain. 
A. Incongruent effect, B. Euphoria, C. Labile effect, D. Split personality
C: Labile effect
Answer: C: Labile effect 
Explanation: Labile effect