题目

根据短文内容，从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。At the mention of Beijing, the first thing a lot of people think about is the Beijing Hutongs. A Beijing Hutong is not only an important part of the city but also a means of transportation. . And it is an important stage for historical and cultural development of the city as well.. It is on the west side of Qianmen Street, just a few hundred metres from the south of Qianmen. This 270-meter-long and 9-metre-wide street has dozens of shops and service establishments.Dashilia20、下列各式从左到右的变形，正确的是（　　）A、-x-y=-（x-y）B、-a+b=-（a+b）C、（y-x）2=（x-y）2D、（a-b）3=（b-a）3