Question

refer to the graph below.
us house and senate reelection rates, 1984–2016
source: center for responsive politics
which of the following is a chief cause for the trend shown in the line chart?
incumbents do not need to raise as much money as challengers.
citizens are familiar with incumbents, who use their office for outreach.
unbiased, nonpartisan drawing of congressional districts maintains this trend.
different campaign finance rules apply to incumbents and challengers.

Explanation:

The graph shows high reelection rates for House and Senate incumbents. Citizens' familiarity with incumbents (who use their office for outreach like constituent services, public appearances) makes voters more likely to reelect them. Other options: Incumbents often raise more than challengers (so first is wrong); Gerrymandering (not unbiased districting) affects House, and Senate has no districts (so third is wrong); Campaign finance rules don't differ by incumbent/challenger status (fourth is wrong).

Answer:

B. Citizens are familiar with incumbents, who use their office for outreach.