This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Major Depression, Subject name: Psychiatry
Increased suicidal tendency is associated with - 
Select and explain. 
A. Increased Noraderenaline, B. Decreased Serotonin, C. Decreased Dopamine, D. Increased GABA
B: Decreased Serotonin
Answer: B: Decreased Serotonin 
Explanation: Ans. is 'b' i.e., Decreased Serotonin o Patient with suicide has decreased level of serotonin metabolite (5-HIAA) in urine & plasma. Thus indirectly we can say that suicide is associated wdth decreased levels of serotonin and hence there is a decrease in the level o^ serotonin metabolites.