请教一道逻辑题 - ChaseDream

Because incumbent members of Congress are given a great deal of attention by the news media
and because they enjoy such perquisites as free mail privileges and generous travel allowances,
incumbents enjoy an overwhelming advantage over their challengers in elections for the United
States Congress.
Which of the following, if true, best supports the claim above?
(A) In the last congressional elections, incumbents met with a larger number of lobbyists than did
challengers.
(B) In the last congressional elections, 98 percent of the incumbents in the House of Representatives
who were seeking reelection won.
(C) Incumbent members of Congress are frequently critical of the amount of attention given to them
by the news media.
(D) The support that political station action committees provide to challengers for congressional
seats often compensates for the perquisites enjoyed by incumbent members of Congress.
(E) Of all incumbent senators surveyed before the last congressional elections, 78 percent said that
their challengers did not pose a serious threat to their chances for reelection.

新东方的老师给的答案是a，但本人很不理解；觉得b比较好，因为正是因为incumbent members enjoy,她们才会去申请连任啊！

请有识之士帮我解答一下，谢谢

B---whether the incumbents want to be reelected or not can't explain why they have more advantage in the election.

what if they want to be reelected, but nobody supports them, all the people support their challengers?