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': 'What is the function of WHO collaborating centres? \nSelect and explain. \nA. Contact with ground root workers, B. Collaborative research work, C. Contact with higher officials, D. None of the above', 'role': 'user'}, {'content': "Answer: B \nExplanation: WHO collaborating centres are institutions such as research institutes, parts of universities or academies, which are designated by the Director-General to carry out activities in support of the Organization's programmes.", 'role': 'assistant'}]