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.

1. that the North American Indians have developed advanced full-year calendars basing them
2. of the North American Indians who have developed advanced full-year calendars and based them
3. of the development of advanced full-year calendars by North American Indians, basing them
4. of the North American Indians and their development of advanced full-year calendars based
5. that the North American Indians developed advanced full-year calendars based

Highlight to see answer: E

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