This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pathology
[{'content': 'Which of the following fatty acid is a precursor of arachidonic acid? \nSelect and explain. \nA. Linoleic acid, B. Linolenic acid, C. Oleic acid, D. Palmitoic acid', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Arachidonic acid is a 20-carbon polyunsaturated fatty acid (5,8,11,14-eicosatetraenoic acid) that is derived from dietary sources or by conversion from the essential fatty acid linoleic acid. Ref: Robbins 8th edition, Chapter 2.', 'role': 'assistant'}]