This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: C.N.S, Subject name: Pharmacology
Increased suicidal tendency is associated with alteration in the brain levels of: 
Select and explain. 
A. Noradrenaline, B. Serotonin, C. Dopamine, D. GABA
B: Serotonin
Answer: B: Serotonin 
Explanation: Ans. (B) Serotonin(Ref: KDT 8/e p188)Decreased serotonin levels in brain is associated with depression (and suicidal tendencies) whereas elevated levels of 5-HT are associated with anxiety.