Answer: Urban = Hight Population Density
Suburban = medium density
rural = low density
Explanation: Think of the areas which are described. In a city, people are usually packed in tight areas, such as apartment buildings. Cities usually have the highest population as well. In suburban areas(neighborhoods) there are still a big population but, they are more spaced out. In rural areas(farms, small towns) there are less people. Because of this, they are more spread out.
