This excerpt is from the U.S. Constitution.
Article II, Section 2
He [the president] shall have Power, by and with the Advice and Consent of the Senate, to make Treaties, provided two thirds of the Senators present concur; and he shall nominate, and by and with the Advice and Consent of the Senate, shall appoint Ambassadors, other public Ministers and Consuls, Judges of the supreme Court, and all other Officers of the United States, whose Appointments are not herein otherwise provided for, and which shall be established by Law: but the Congress may by Law vest the Appointment of such inferior Officers, as they think proper, in the President alone, in the Courts of Law, or in the Heads of Departments.
Which fundamental principle of U.S. democracy does this excerpt describe?

A.representative government

B.checks and balances

C.right to a fair trial

D.legislative powers

The balance of powers between the different branches of government are described in this passage from the US Constitution. While the passage most focuses on the power of the executive branch, meaning the president and his appointees, it also describes how the Senate has to consent to treaties by two thirds and that the Senate also provides advice and consent on other executive appointments. The excerpt describes how Congress has the power to decide who should appoint lower officers in the government representing another check and balance to executive power.