Use the quotation below to answer the following question. "Our hearts are sickened, our utterance is paralyzed, when we reflect on the condition in which we are placed, by the audacious practices of unprincipled men...We are constrained solemnly to declare, that we cannot but contemplate the enforcement of the stipulations of this instrument on us, against our consent, as an act of injustice and oppression..."

-- Chief John Ross in a letter addressed to Congress, 1836

The quote above directly relates to which of the following events?

a. the Louisiana Purchase
b. the Lews and Clark Expedition
c. the Homestead Act
d. The Trail of Tears