A.spreading viruses
B.changing information
C.making a new password
D.manipulating codes

A.active hackers are more skilled.
B.passive hackers have more intense personalities.
C.active hackers do damage.
D.passive hackers are caught more easily.

A.need
B.start
C.encourage
D.design

A.need
B.start
C.encourage
D.design

A.They reduce the impact of transportation on climate.
B.Urbanization create severe problems in such cities.
C.There is more pollution in cities.
D.People in the cities face daunting challenges.

A.urban expansion
B.socio-economic disparities
C.disease
D.unsanitary conditions

A.It minimizes risks for economic, cultural and societal development.
B.It makes water supply system effective.
C.Weather and climate in the city will be much improved.
D.People may come up with new ideas for innovation.

A.Urbanization brings important benefits for development as well.
B.54% of the world's population will live in cities by 2050.
C.Risks cannot be addressed effectively no matter how well cities are governed.
D.Rapidly increasing population density can help solve poverty.

A.aimed at
B.dealt with
C.added to
D.agreed on

A.Poverty may be a foregone conclusion of unplanned urbanization.
B.Diseases are caused by people migrating to cities.
C.Urbanization can solve the problem of environmental pollution in cities.
D.The increasing number of people in cities can create more employment.