The factor that contributed most significantly to the differences among Texas American Indian cultures is the —

They had different plant and animal resources available to them.

Explanation:

Various factors contributed to the difference in the cultures of the native Indians in Texas. Some of which deals with the fact that some migrated from another place to the area.

However, most significantly to the differences among Texas American Indian cultures is the "They had different plant and animal resources available to them."

This was evident in that, some groups in these regions were nomadic like the Apaches, due to the availability of Horses, while some others are predominantly farmers such as Caddoans.

Some groups were even raiders, raiding their neighboring tribes for foods because they do not have edible plants or no fertile land.

While some were hunters and gatherer in nature. All of these differences in their ways of life can be attributed to "different plant and animal resources available to them."

"choosing is refusing" means individuals face an opportunity cost with each decision they make. economists state that every decision involves trade-offs. opportunity cost is the least desirable alternative given up as a result of a decision.

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