This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Neurotic, Stress Related and Somatoform Disorders, Subject name: Psychiatry
Which of the following is considered as an anxiolytic substance? 
Select and explain. 
A. Caffeine, B. Cholecystokinin, C. Neuropeptide Y, D. Carbondioxide
C: Neuropeptide Y
Answer: C: Neuropeptide Y 
Explanation: Anxiolytic substances Anxiogenic substances Benzodiazepines Selective Serotonin Reuptake Inhibitors Beta-blockers Neuropeptide Y Buspirone Carbon dioxide Cholecystokinin Flumazenil Caffeine