This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Histamine, 5-HT and PGs, Subject name: Pharmacology
[{'content': 'Prostaglandins are obtained from:- \nSelect and explain. \nA. Stearic acid, B. Arachidonic acid, C. Linoleic acid, D. Linolenic acid', 'role': 'user'}, {'content': 'Answer: B \nExplanation: NOTE:-Arachidonic Acid is a 20 carbon fatty acid. No.of double bonds in Arachidonic acid =4 Key points to Remember Linoleic Acid- Most essential Fatty Acid. Richest source of linoleic Acid - Safflower oil. Richest source of Arachidonic Acid - Safflower oil. Richest source of Linolenic Acid - Flaxseed oil.', 'role': 'assistant'}]