Based on this information, the case of united states v. nixon (1974) dealt with what constitutional principle? a) suffrage b) federalism c) checks and balances d) separation of powers

Separation of power

The supreme court unanimously ruled that the president does not have any executive privilege against subpoenas and other civil action proceedings which ultimately underlined the power of each organs of the government in which was a historic ruling that defined the independence of the courts.

Y=-121/7+11/7x i think this may be wrong