Bunuel
Mountain County and Sunrise County are two comparable counties, with similar numbers of registered voters. Both are in the same region of the state. In both counties, about 60% of the registered voters are registered Republicans, and almost all others are registered Democrats. In 2005, Republican candidate Alf Landon ran for supervisor of Mountain County, and Republican candidate Thomas Dewey ran for supervisor of Sunrise County. Both took similar stands on issues, and both ran against conservative Democratic candidates in the general county-wide election, and none of these four candidates was an incumbent at the time of this election. The Republican Congressman representing Sunrise County endorsed Mr. Dewey, but the Republican Congressman representing Mountain County refrained from endorsing Mr. Landon. Mr. Dewey won his election, but Mr. Landon lost his election. Clearly, the endorsement positions of the respective Congressmen were the deciding factors in these elections.
In evaluating the argument, it would be most useful to know which of the following?
(A) How these two counties have voted in US Congressional and US Presidential elections over the past decade
(B) What stands Mr. Landon and Mr. Dewey took on issues considered most important by registered Democrat voters
(C) How well Congressmen, involved primarily in national politics, are informed of the details of local politics within a single county.
(D) How typical it has been throughout the state, in the past decade, for a Congressman to endorse a county supervisor candidate running in his Congressional district.
(E) How many voters in each of these two counties were aware of their respective Congressman's endorsement positions.
Magoosh Official Explanation:
The counties are similar, the candidates are similar, and the elections seemed quite similar up until the difference of endorsements. Mr. Dewey was endorsed, and Mr. Landon was not. Dewey won, and Landon lost. The argument attributes the difference in election outcome to the difference in endorsements, and we want to evaluate this argument.
(E) is the credited answer. This is crucial: if voters were not aware of the endorsements, then those endorsement could not influence how they voted.
(A) is not necessarily relevant. Presumably both counties voted Republican in most elections, since both are heavily Republican. It's unclear how that would explain anything about the different results in these two elections.
(B) is also not directly relevant. Both counties have a sizeable majority of Republicans. If all voters had simply voted along party lines, both Dewey and Landon would have won. Since a Republican candidate lost, this must mean that many Republicans voted against him. Presumably neither one of these candidates received substantial support from the Democrats in his county.
(C) is entirely irrelevant. National–level politicians often endorse local candidates without having a clue about the local situation. The national-level politician has name-recognition and prestige: these make such an endorsement powerful, regardless of how well informed the national-level politician is about the local political scene.
(D) is vaguely relevant --- if endorsement from Congressmen always happened in both counties, or never happened in either county, then one of these two elections would constitute an exception to the general rule, and that could be notable. But, if endorsements happened irregularly, with no general rule, then it would be considerably harder to argue that this unpredictable pattern was decisively relevant to this argument. Because we don't know what the past pattern of endorsement was, we don't know how relevant this piece of information would be.
BTW, cool historical facts, not at all relevant to the GMAT: Both Alf Landon and Thomas Dewey were unsuccessful Republican candidates for US President. Landon lost to FDR in 1936. Dewey lost to FDR in 1944 and to Truman in 1948 --- his name was featured prominently in one of the famous "bloopers" in US presidential election history.