I'm not 100% sure... but I would say B.
The correct answer is C) comprise several edge cities with independent business cores.
The modern urban areas have central city and multiple other edge cities around it, even though the central city is the biggest and most influential, all of the edge cities have separate business cores and all institutions needed for an urban area. They are in very close proximity to the central city and are well connected in every department.
Answer:
Smallpox has had a major impact on world history, not least because indigenous populations of regions where smallpox was non-native, such as the Americas and Australia, were rapidly decimated and weakened by smallpox. During the 18th century the disease killed an estimated 400,000 Europeans each year, including five reigning monarchs, and was responsible for a third of all blindness. After successful vaccination campaigns throughout the 19th and 20th centuries, the WHO certified the global eradication of smallpox in December 1979. Smallpox is one of two infectious diseases to have been eradicated.
Explanation:
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