8.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, (E) which is believed to be
答案C,请问如果去掉and it is,只有believed to have been可不可以作为正确答案?