The riot（暴乱） is said __________ by the government’s negligence o

The riot（暴乱） is said __________ by the government’s negligence of the people’s welfare.
A、to have been caused
B、being caused
C、to be caused
D、to cause
【正确答案】：A
【题目解析】：be said to据说......，be caused by意为”由......造成的“。