A
本题考查倍数的表达方法：倍数+as+形容词 或 副词 的原级+as……,再如：This room is twice as big as that one.
句式分析：这是主语从句, it 是形式主语, is said 是谓语,that 从句是真主语,因为that从句太长为了避免头重脚轻,所以用it放在句首代替that从句.