Sentence Correction (SC) | Re: A calendar stick carved centuries ago by the Winnebago tribe

(A) that the North American Indians ((have)) developed advanced full-year calendars basing them - it is something done in the past. So use of "have" is incorrect.

(B) of the North American Indians who have developed advanced full-year calendars and based them - it is only one part.... awkward.

(C) of the development of advanced full-year calendars by North American Indians, basing ((them)) - them seems to refer to North American Indians rather than calendars.

(D) ((of the North American
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