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: Social & Preventive Medicine
[{'content': 'Predominant type of immunoglobulin in human milk: \nSelect and explain. \nA. Ig A, B. Ig G, C. Ig M, D. Ig D', 'role': 'user'}, {'content': "Answer: A \nExplanation: In cow's milk the predominant type of immunoglobulin is Ig G, while in human milk it is Ig A. Ref: Nutrition and Child Development, K.E. Elizabeth, 4th edition pg: 22", 'role': 'assistant'}]