Answer:
(A) the land runs prompted the end of peaceful co-existence between whites and blacks during this time period
Step-by-step explanation:
The time period starting from 1866 upto 1899, demand for food in Eastern part of the cities and railroads in Kansas was ought to be met by cattle ranches in Texas Storve. Later developing as cow boys, the products were either transported to north or they settled without valid permissions in Indian territory.
The increased influx of white settlers prompted the US Govt to establish the Dawes act in 1887, hence dividing the land of tribes which in turn led to the premature end of peaceful existence between white and black people.