Shenzhen's fast development has made it become China's most crowded city! There are about 15 million people living on its 1991square kilometers. On each square kilometer averagely live 7500 people. It is 1080 more than that in Hong Kong, and nearly 800 more than that in Guangzhou.
Besides, Shenzhen owns 2 million local vehicles, and about 300000 vehicles from other places also run on the local roads every day. The total length of the city's road is 6041 kilometers. It means each resident only owns 0.58 meters of road!
As a result, the city is facing serious environmental and resource problems. One of the problems is water shortage. The amount of fresh water for each person of the city is only 25% of the country's average. What's more, most of the water drunk by Shenzhen people comes from other areas.
According to the passage, which of the following makes Shenzhen so crowded?

A．Shenzhen has not enough water.

B．There are too many people

C．Shenzhen is developing very fast

D．Shenzhen is too small

There are _______ people living in Shenzhen now.

A．about 1991

B．about 15000000

C．about 150000

D．about 300000

In Hong Kong, there are _______ people on every kilometer?

A．about 7500

B．about 1080

C．about 800

D．about 6420

Which problem in Shenzhen is not mentioned in the passage?

A．Traffic accidents.	B．Water shortage.
C．Environmental problems	D．Population problem.

Which is the best title for this passage?

A．Largest Population in China.

B．Biggist Problems in Shenzhen

C．Busiest Roads in Shenzhen

D．Most Crowded City in China