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': 'The rate adjusted to allow for the age distribution of the population is - \nSelect and explain. \nA. Perinatal mortality rate, B. Crude mortality rate, C. Fertility rate, D. Age standardized mortality rate', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Age adjustment or age standardization removes the confounding effect of different age structures of two different population and yields a single standardized rate, by which the mortality experience can be compared directly.', 'role': 'assistant'}]