Native American Settlement North of Present-Day Mexico Had Limited Impact

Native American settlement north of present-day Mexico had limited impact on the land mostly because

A) Native tribes practiced an early form of conservationism.
B) Native religions commanded minimal interference with the natural environment.
C) Natives in the northern part of the continent were not familiar with agriculture.
D) Their numbers were comparably small for the vast stretch of land they occupied.
E) Prior to European arrival, native Americans lacked the tools and machinery to significantly shape their landscapes.