Thanks for posting - you know, this is one of those study situations in which you may lose the battle but set yourself up to win the war. The way you worked to eliminate choice A is exactly what we'd want you to do on the GMAT: look for a reason that an answer choice to an Inference problem is 'not necessarily true'.
The LSAT is a little more nuanced in its CR than is the GMAT (but then again the LSAT doesn't have math at all...), so this may be one of those cases in which LSAT questions are good study for the GMAT but may not be identical. For more on that topic, I highly recommend that you check out this blog series from instructor David Newland: http://www.beatthegmat.com/lsat-to-study-for-the-gmat-part-2-critical-reasoning-t69915.html
Here, I'd still argue that choice B isn't directly supported by the information (the author proposes two solutions - jail or re-education - but that doesn't mean that either is the most effective. What if electroshock therapy was the most effective, but considered too expensive or too inhumane? Just because the author didn't suggest it doesn't mean it's not an option...). And the way that the question is phrased ("provide the MOST support...") there may be a way in which the the answer doesn't have to be 100% (again, this is using LSAT burden-of-proof standards, of which I don't 100% know for certain). A is definitely pretty-well supported even it's not airtight, and I don't think you can say that about any of the others.
One more consideration - in the question the phrasing is "...it is (1) always (2) almost impossible...", but in your explanation you reverse the order ("it is (1) almost (2) always impossible...". Is it possible that the source of this question mistyped a keyword here or there? I don't know that that ordering is enough to change the "must be true" standard of proof here, but the fact that the question can be modified slightly in one transcription to the next means that there's a chance it was done before you received it, too...