Read the passage, and choose the correct answer A, B, C or D for question

A striking feature of Viet Nam’s remarkable progress over the last few decades is the rapid pace of urbanisation. In 1986, there were fewer than there are 30 million urban residents. Today there are 30 million. Cities have become strong growth forces, with urban areas growing twice as fast as the national average rate, and contributing over half of the country’s gross domestic product.

Viet Nam needs to reshape its urbanization process to create more efficient cities - cities that have sufficient population densities are well connected internally and regionally, and well managed. In addition, in line with Viet Nam's strong preference for social equity, cities will need to ensure inclusion of all residents, with no groups or area “left behind."

Meanwhile, rural residents increasingly lag behind their urban counterparts in income and access to services, leading many to migrate to cities. Migration presents challenges for urban management but also opportunities to enhance labor mobility. Fortunately, these trends can be reversed.

For example, four years ago, Alley 76 in Binh Thanh district, Ho Chi Minh City was only narrow enough for one motorbike to get through. Store owner Bui Thi Mai knows how a clean and efficient city can make or break a business. When it rained, the alley was often flooded with floating garbage and mosquitoes. Crime was increasing. Today, after undergoing major upgrading under an urban renewal project, the street is cleaner, safer and trucks carry goods to her door. Her family income has soared and her life has been completely changed.

Urbanisation in Viet Nam has _______.

• A. 
  mainly contributed to the country’s GDP
• B. 
  promoted the country’s economy twice as fast as before
• C. 
  made rural areas develop along with urban ones
• D. 
  made urban areas develop faster than the average