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': "Diffuse erythema (pin-point petechiae) and white patches in smoker's palate occur due to \nSelect and explain. \nA. Complete obstruction to minor salivary gland orifices, B. Keratinization with partially occluded minor salivary glands, C. Diffuse parakeratinization of the palate, D. Excessive orthokeratinization of the palate", 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]