The excerpt is from the 1855 Treaty with the Yakama.

Nor shall any white man, excepting those in the employment of the Indian
Department, be permitted to reside upon the said reservation without permission of the tribe and the superintendent and agent.

–Treaty with the Yakama,
1855

Which action would most likely violate this condition of the agreement?

teachers being employed by the Indian Department and living on Yakama lands
traders exchanging goods with Yamaka Indians at tribal-approved trading posts
gold miners entering Yakama lands on their way to the gold rush in Canada
farmers establishing farms on Yakama lands with permission from tribal leaders