This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Nervous system, Subject name: Physiology
The principal polypeptide that increases food intake are all except 
Select and explain. 
A. Neuropeptide Y, B. Leptin, C. Orexin A, D. Ghrelin
B: Leptin
Answer: B: Leptin 
Explanation: An orexigenic, or appetite stimulant, is a drug, hormone, or compound that increases appetite and may induce hyperphagia. This can be a naturally occurring neuropeptide hormone such as ghrelin, orexin or neuropeptide Y, or a medication which increases hunger and therefore enhances food consumption Ref: guyton and hall textbook of medical physiology 12 edition page number:811,812,813