Answer:
Majority leader.
Step-by-step explanation:
The Majority leader is the head of the Senate. He is designated by a vote of the party senators who are in majority in the Senate. He opens and ends sessions, he controls the parliamentary agenda. Nevertheless, the function of president of the Senate belongs to the vice president, he may join the sessions and vote. The majority whip is the second-in-command, so to speak, of the majority party in the Senate, the immediate leader of all his or her fellow party senators.