专业、全面、易懂的全领域名词百科

TheBentPyramidoutsideCairo__________ancientEgypt’sfirstattempttobuildasmooth-sidedpyramid.

题型：单选题

选项

A. has been believed to have been

B. was believed to be

C. is believed to have been

D. is believed to be

正确答案：C