Final answer:
Elimination of the seniority rule would most likely increase the influence of committee chairpersons, who hold significant authority over committee functions and decisions in the legislative process.
Step-by-step explanation:
If the seniority rule were to be eliminated, the group most likely to gain greater influence over the process would be c) Committee chairpersons.
Committee chairs hold significant power within the legislative structure. They control the committee's budget, schedule meetings and hearings, and have the authority to decide whether a bill will be considered.
Without the seniority rule, junior members, external stakeholders, and newcomers would still face significant obstacles to influencing the legislative process due to a lack of experience, institutional knowledge, and internal connections that committee chairs possess.
The seniority rule exemplifies a form of authority based on years of service and other factors, often leading to an incumbency advantage for legislators. This can detract from the responsiveness to constituents' demands.
Committee chairs, having gained their positions through this seniority system and understanding of internal procedures, would likely enhance their status and influence in the absence of the seniority rule, in line with the insider-outsider model.