How are the senate leaders chosen?

they are appointed by the president of the senate.
they are elected within each party.
they are elected by the whole senate.
they are appointed by the president pro tempore

Option 2: They are elected within each party.

At the beginning of each Congress, the parties' members in the Senate choose their own leaders which shall protect their rights and interests on the Senate floor. Since the 1920s, the Republicans and Democrats are the first floor leaders of the U.S.

Depending on which party is in power, one serves as majority leader and the other as minority leader. The majority leader, whose power in the Senate is equal to the power of the Speaker of the House, is responsible to schedule the daily legislative program and, along with the minority leader, it creates the unanimous consent agreements that govern the time for debate.

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