题目内容:
Riotpolicearecalledin_______.
A.toseparatetheopposingfansinsidetheground B.asaprecautionagainsttroubleinsidetheground
C.tostopfightingoccurringoutsidetheground
D.asaprecautionagainstfightingoutsidetheground
参考答案:
答案解析: