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: Pediatrics
[{'content': 'A child has recently developed mouthing but has not developed stranger anxiety, likes and dislikes for food. What is the most appropriate age of this child? \nSelect and explain. \nA. 3 months, B. 5 months, C. 7 months, D. 9 months', 'role': 'user'}, {'content': "Answer: B \nExplanation: Since the child in question has developed mouthing (develops between 3-6 months) but has not yet developed stranger anxiety or likes and dislikes for food which are developed at 7-8 months and in first year of life respectively, the appropriate age of this baby should be 5 months. Ref: Early Years: Child Care and Education, By Maureen O'Hagan, Maureen Smith - Pg 16; Nelson 17th Edition, Page 34, 82; Essential Pediatrics, OP Ghai - 6th Edition, Page 44, 47", 'role': 'assistant'}]