I think I have learned the key to LR.

Overall you can classify most LR questions by the type of answer they are looking for.

Powerful Question Types

Strengthen

Weaken

Sufficient Assumption

Paradox

Provable

Necessary Assumption

Flaw

Main Conclusion

If you focus in on these chareteristics of correct answer choices you will be able to rule out most of the time 3/5 answer choices. Leaving you with a 50 percent chance to get the answer correct. Once you've done this you look at the two answer choices and look to see whats wrong with one rather than whats correct about one.