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: Dental
[{'content': 'Which type of cells are most numerous in gingiva \nSelect and explain. \nA. Melanocytes, B. Keratinocytes, C. Giant cells, D. Polymorphonuclear leukocytes', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]