问题
n the United States, St Louis has nowbecome the 4th largest city.
A:It is the 24th biggest city
B:It was the 24th biggest city
C:Before the 24th biggest city
D:Once the 24th biggest city
B:It was the 24th biggest city
C:Before the 24th biggest city
D:Once the 24th biggest city
正确答案是：
