As with all Critical Reasoning questions, your first task is to break down the argument, by labeling each part as either a premise or a conclusion.

With Conclusion Strengthening questions your job is to identify a new premise which strengthens the argument's conclusion by finding the answer choice that does one of the following:

1. Identifies and strengthening an assumption underlying the conclusion
2. Strengthens or validates the conclusion itself
3. Rules out alternative explanations - an answer choice can strengthen a conclusion by saying that a potential "weakener" is NOT true
4. Citing similar cases in which the conclusion holds

With Conclusion Weakening questions your job is to identify a new premise which weakens the argument's conclusion by finding the answer choice that does one of the following:
1. Questions or invalidates an assumption underlying the conclusion
2. Questions or invalidates the conclusion itself
3. Provides an alternative explanation for the conclusion
4. Cites similar cases in which the conclusion does not hold

strengthen types - supporter and defender.

supporter - types where there is a reasoning gap.This gap fits between premises and conclusion.
One needs to focus on this reasoning gap to strengthen the conclusion.

An assumption types question also at times focuses on this gap too.

defender - types where there is no gap in the reasoning and there has to be an external element supporting the conclusion.

meaning is cause 1 => effect. then the answer option should show, 1. effect !=> cause 1.
or 2 no other cause except cause 1 is leading to effect.

weakening - you need to focus on the conclusion and check the effect of the answer option on the conclusion. An external element might also be brought into picture to weaken the conclusion.

Negating an answer option helps a lot.
for strengthening type,negating should weaken the conclusion and for weakening type it has to be a vice-versa.

No fact test, Negation and conclusion have to be used efficiently for these 3 types of questions.

thanks guys for help


another thing is that, what would be the strategy for the causal-effect relationship in case of strengthen, weaken, and assumption problems

regards nafi