Pre-thinking an assumption can really help you stay on track and identify the correct answer quickly. There may be multiple assumptions but pre-thinking is useful in most cases because you understand the argument well before jumping into the options.

Argument:
There are districts controlled and the President and there are some controlled by the opposition parties. The President canceled some projects. 90% of those were located in the opposition party districts. So opposition has been crying foul. The secretary is defending the President. He says that all of these were identified as wasteful by non partisan auditors.
Conclusion: the President's choice was clearly motivated by sound budgetary policy, not partisan politics.

Now we have to think an assumption for this conclusion.

Think of a political argument in which you are taking part. You have to assume that whatever the other person says is the truth. You have to put forward a counter point keeping that in mind. So the other person says, 'all of these were identified as wasteful by non partisan auditors.'
The question that should come to your mind is: which other projects did the non partisan auditors identify as wasteful? Say, they identified 20 wasteful projects. 12 from the President's districts and 8 from the opposition's. What if the President chose all the projects to be canceled from the 8 wasteful projects of the opposition's districts? Everything said in the argument stays true but the conclusion becomes invalid. The President would have been motivated by partisan politics in that case.
The assumption you are looking for: Not many of the projects identified as wasteful were from the President's districts.

Hence (B) is your assumption.
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Opposing argument: President carries partisan politics.
Fact: 90% project cancelled are by opposing party.
Counter argument: All the cancelled project have been identified as bad by a nonpartisan auditor.

What is the missing link here?

What if the auditor has identified many projects by the controlling party as well as by the opposing party as wasteful and the president only cancels the opposing party ones?

To make the press secretary's argument work one has to make the assumption that there aren't a lot of bad projects in the controling party district in the auditor's report.

Therefore (B) would be the correct answer.

IMO its B)...negate B) => "The scheduled highway projects identified as wasteful in the report were mostly projects in districts controlled by the President's party". so the author was not driven by sound budgetary policy, but by the fact that most of the wastefult projects are in his districts. so he is partisan.

...negate E) "Reports by nonpartisan auditors are generally regarded by the opposition parties as a source of objective assessment of government projects". when even the oppositon thinks that this report is objective, then it should be fine to conclude that the president is not partisan but just a politician who is concerned about the economy.

A. Canceling highway projects was not the only way for the President to punish legislative districts controlled by opposition parties. Logical error. Does not strengthen the argument. Just because canceling the projects was not the only option to be vindictive, does not mean that the action itself was not vindictive.
B. The scheduled highway projects identified as wasteful in the report were not mostly projects in districts controlled by the President’s party. Most cancelled projects were in opposition districts (existing premise), but most of the projects identified as wasteful were also in opposition districts (this choice). This combination strengthens the argument. Correct.
C. The number of projects canceled was a significant proportion of all the highway projects that were to be undertaken by the government in the near future. Out of scope. Incorrect.
D. The highway projects canceled in districts controlled by the President’s party were not generally more expensive than the projects canceled in districts controlled by opposition parties. Weakens the argument, rather than strengthen it. Incorrect.
E. Reports by nonpartisan auditors are not generally regarded by the opposition parties as a source of objective assessments of government projects. Weakens the argument, rather than strengthen it. Incorrect.

Thanks for sharing.

Premise of the argument: "all of the canceled projects had been identified as wasteful in a report written by respected nonpartisan auditors."

Conclusion of the argument: "So the President’s choice was clearly motivated by sound budgetary policy, not partisan politics."

In the assumption questions, the conclusion follows given the premise and the unstated assumption. In such questions, the premise is not complete. It needs something more which is the assumption for the conclusion to logically follow. In the above question the premise says that all the cancelled projects were wasteful. Choice B completes that by saying that all the wasteful projects were indeed cancelled and were not based on partisan politics. Only then the conclusion that the decision was based on sound budgetary policy follows.
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B is clearly the answer. The other options go in other directions respect the argument at stake
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Lets talk numbers!
Lets assume,
No of wasteful project districts=200
President's party districts=110
Opposition districts=90
Now lets say that the president cancelled 100 projects with 90 districts belonging to opposition and 10 of his own (so that it becomes 90%)
Now clearly the president is NOT fair isnt it?
That is exactly what B says!
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The Press Secretary goes on to defend the president's choice... That the cancelled projects are supported by nonpartisan auditor and that the choice is objective and not biased...

A. Canceling highway projects was not the only way for the President to punish legislative districts controlled by opposition parties.
Other ways to punish legislative districts is irrelevant to the argument...

C. The number of projects cancelled was a significant proportion of all the highway projects that were to be undertaken by the government in the near future. This is attempting to introduce an extended story to the argument... which means it was not assumed by the Press Secretary...

D. Nonpartisan auditors were President's friends.
Friendship doesn't make the nonpartisan report biased... two friends can have totally different stand on politics but still be friends... to extend this choice means it is not the assumption...

E. Reports by nonpartisan auditors are not generally regarded by the opposition parties as a source of objective assessment of government projects.
what the opposition parties think of the auditor is irrelevant... to what the auditor really is.. did the auditor really gave an honest report or not... that is the line of argument by the Press Secretary... as support that the president's choice is not biased...


Answer:

B. The scheduled highway projects identified as wasteful in the report were not mostly projects in districts controlled by the President's party.
If most of the projects identified as wasteful are district controlled by President then the Press Secretary need not to worry about defending the President's choice...

Look at things from a critical viewpoint. Read articles related to critic's views, letters to the editor, political dialogues - anything and everything that will help you understand the various different view points. Try to find out what can strengthen/weaken others' arguments. Imagine that you are debating with someone - you need to think of counter points. It comes with practice.
But mind you, don't waste too much time trying to pre-think. If nothing comes to mind, just move on to the options. The options will give you a clue.
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Premise: All of the projects cancelled by the president had been identified as wasteful in a report written by respected nonpartisan auditors.
Conclusion:the President's choice was clearly motivated by sound budgetary policy, not partisan politics.

We need to look for an assumption that makes the conclusion definitely follow from the premise. What the premise says is that the cancelled projects have been identified as wasteful. But from this, the conclusion does not definitely follow. This is because even though all the cancelled projects have been identified as wasteful it does not mean that all the wasteful projects have been cancelled. Choice B fills that gap as it says that most of the wasteful projects are not in districts controlled by the president's party. Because if it were, then 90% of the cancelled projects being in opposition controlled districts, the president would be considered partisan.
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I am not able to understand how B is correct

B.The scheduled highway projects identified as wasteful in the report were not mostly projects in districts controlled by the President's party.
This means, the projects that got cancelled are from districts which are not ruled by president's party. If this is assumption, then it could be because of partisian politics.
Can anyone explain what I am missing here?

No. The statement in bold is given to you in the argument. You are given that the projects that got cancelled were mainly from oppositions' disticts. What we are assuming is that the projects identified by the report as wasteful were not mainly from the President's districts.
Out of the 10 projects cancelled, 9 are from oppositions' districts. All these 10 projects were identified as wasteful by non partisan auditors. We are assuming that non partisan auditors did not identify 20 other wasteful projects - all of which belonged to the President's party but were not cancelled. We need to assume this if we are to say that the President is motivated by sound budgetary policies.
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I'm still confused though.
If the assumption was "many of the projects identified as wasteful were from the President's districts" instead of "NOT many of the projects identified as wasteful were from the President's districts", that would have been more explicit IMO. The projects that were deemed wasteful turning out to be from the president's district would've definitely proved the point that the president didn't have any political motivation behind the cancellation.

However the OA (b) is stating that "not many were from the the president's district", which implies many projects that were cancelled was indeed from districts other than from the president's. Please correct me if I'm wrong, but somehow this assumption seems a bit weak to support the Scretary's claim.

What shows political vengeance on the part of the President? Cancellation of projects of opposition districts.
The President claims that they were wasteful so there is no politics involved.
The conclusion of the argument is "President is motivated by policy, not politics."

What do we NEED to be true if we are to say that the President is motivated by policy only? Since most of the cancellations were from opposition districts, it would make sense only if most wasteful projects were from opposition districts only. We need this to be true (i.e. it is an assumption) to establish the conclusion that the President is not politically motivated.
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Thanks! I finally understand this one after reading the explanation several times. Let me whether I can explain it well.

The premise states that 90% of the cancelled projects were from the opponents' districts and that ALL of the cancelled projects were wasteful. For the President to be fair, we would have to show that he did not choose to ignore wasteful projects from his party's districts. If a sizable proportion of wasteful projects were from his party's districts and they were not cancelled, he would be biased. B clearly defends against this possibility.

can anyone explain why A option is not correct.

Whether there are other ways to punish legislative districts controlled by opposition parties is immaterial. The argument doesn't say that the President must punish legislative districts controlled by opposition parties. To assume that 'the President did not cancel the highway projects to punish' means 'he must have other ways to punish' is not only unwarranted but also unethical! Option (A) does not need to be true for the argument to hold and hence it is not an assumption.
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Hi Karishma, to me answer choice (B) looks more like an inference; since second line very clearly says 90% of cancellations are from the districts controlled by the opposition. This indirectly means that most of the cancellations were not from the president's districts i.e. answer choice (B), then why should we classify it as an assumption and not inference?

On the contrary, (A) looks a better assumption to me if you apply negating rule.

Please clarify my doubts. Thank you.

Another way to figure out an assumption is inserting it in the argument with the premises and then checking whether the conclusion needs the assumption.

Argument:
There are districts controlled by the President and there are some controlled by the opposition parties.
The President canceled some projects.
90% of those were located in the opposition party districts. So opposition has been crying foul.
The secretary is defending the President. He says that all of these were identified as wasteful by non partisan auditors.
Most of the wasteful projects identified were from opposition's districts. (That is why most of the canceled projects are from opposition's districts)

Conclusion: the President's choice was clearly motivated by sound budgetary policy, not partisan politics.

Mind you, you already have the conclusion of the argument and that is "President's choice was clearly motivated by sound budgetary policy, not partisan politics". But to prove that this is true, we need to know that most wasteful projects identified were from opposition's districts. What if the non partisan auditors identified 100 projects as wasteful out of which 90 were from President's districts but the President chose to cancel the rest of the 10 wasteful projects (which were from opposition's districts). In this case, the President is motivated by politics, right? So we need to know that the wasteful projects were predominantly from opposition's districts only.

As for why (A) is not an assumption, please see my post right above yours.
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