A. assistant party leaders in each house whose jobs include ensuring that party members are present for floor votes and prepared to vote as the party prefers B. the most powerful leader of the House of Representatives; this person refers bills to committees for consideration and appoints members of the majority party to sit on some of the most powerful House committees as well as all members of select and conference committees C. leader of the minority party in each house, responsible for marshaling support for the party's agenda D. the second highest ranking official in the U.S. Senate; this position most often goes to the member of the majority part who has served the longest E. leader of the majority party in each house, responsible for marshaling support for the party's agenda; in the Se