Câu hỏi:

Read the passage. Circle the best answer A, B, C, or D to each of the questions.

My city has been changing since the municipal authority had a plan to renovate the canal systems. The project cost a huge amount of money which was from the support of the world bank and the city’s budget. Before the renovation, the canal was the dirtiest place full of rubbish along its sides. Many ramshackle shacks were built to be shelters of the impoverished working families migrating to this city to earn their living. Household wastes were directly dumped into the canal, resulting in the very contaminated environment. It was said that the very unpleasant smell releasing from the canal was unable to be eliminated, and the living condition there would not be better. However, thanks to the advanced technology and methods as well as the city authority’s effort, everything has been changing. There is no longer the disgusting smell or shabby houses along both sides of the canal. Instead, the road running parallel to the canal is now full of shade of greenery and the water now is so clean that it is a friendly habitat for a variety of fish. The residents now can walk or do morning exercise on the sidewalks along the banks to enjoy the fresh atmosphere. Former inhabitants are also relocated in new apartments with much better living conditions than before. The canal creates not only a beautiful urban landscape, but also brings a lot of economic benefits to local dwellers. Because of its reformation, the city is changing fast too.

The main topic of the passage is about ______________.