大全第一题就卡了，求解

1.        A “calendar stick” carved centuries ago by the Winnebago tribe may provide the first evidence that the North American Indians have developed advanced full-year calendars basing them on systematic astronomical observation.

(A) that the North American Indians have developed advanced full-year calendars basing them

(B) of the North American Indians who have developed advanced full-year calendars and based them

(C) of the development of advanced full-year calendars by North American Indians, basing them

(D) of the North American Indians and their development of advanced full-year calendars based（E）

(E) that the North American Indians developed advanced full-year calendars based

E前面部分我都比较明白，就是最后based不懂，做啥成分呢？basing 和based区别啥？我刚开始，请大家多包涵我问题。