A huge flying
reptile that died out with the dinosaurs some 65 million years ago, the
Quetzalcoatlus had a wingspan of 36 feet, believed to be the largest
flying creature the world has ever seen.
(A)
believed to be
(B)
and that is believed to be
(C)
and it is believed to have been
(D)
which was, it is believed,
答案是C,我不明白A为什么不对。是因为A选项confusing吗？还是be应该用现在完成时？
（C）
(E)
which is believed to be | 
