The correct answer to this open question is the following.
Although there are no options attached we can say the following.
What Turner's comment wanted to say with "the frontier was a meeting point between savagery and civilization" was that the white man was a civilized individual capable of many things due to his intelligence. Different was the case of the Native American Indian tribes that he considered them to be savages with different customs and capacities compared to the white man.
I do not agree with his statement. It had racist connotations and that was not correct. I could say that his statement was arrogant and reflect the wrong idea of many white people of the time.
The fact the Native American Indians were not "modern" in the white people concept, does not mean they were primitive or savage. It simply means that they were different, living under different conditions.
Indians understood and respect mother nature because it was the provider of everything: food, water, air, land.
The whites wanted more land to exploit the raw materials and natural resources to make big profits. On the other hand, Indians loved and respected nature and considered it sacred land.