Which of the Following Represents a Threshold for an Urban

Which of the following represents a threshold for an urban entity?

A) For Canada, it is 1,000 people and a population density of 400 per square kilometre.
B) For Botswana, it is 10,000 people and at least 75 per cent of the economic activity is non-agricultural.
C) For India, it is 25,000 people and does not include populations on the city limits.
D) For Beijing, it is 20,000 people and a population density of 4,000 per square kilometre.
E) All of the above