Despite the negative image of nuclear energy, actually its public safety risks are no greater than ________ of fossil fuels.  [ ]

A. one

B. that

C. them

D. those

直肠镜、乙状结肠镜、纤维光束结肠镜检查最危险的并发症是

A．肛门撕裂引起大便失禁

B．引起直肠大出血

C．交叉感染及癌细胞种植性转移

D．引起直肠穿破

E．引起内痔出血