The correct options are
A Kolkata
B Delhi - National Capital Region
D Boston - Washington DC Region
A megalopolis is an example of an urban settlement. It is typically a region which includes two or more adjacent cities. A megalopolis can have a total population of about ten million people. For example, Kolkata in India is the largest urban area to be considered a megalopolis. The NCR (national capital region) of Delhi consists of areas from Rajasthan, Uttar Pradesh, and Haryana. The area made up by the cities between Boston and Washington DC is also known to be a megalopolis.