Hi Alberto and medialaw,
Just to address the Parallel question, the fact that they are abstract is actually really good for you! It means you don't have to worry so much about the topic details and can instead focus on the structural issues. If we were analyzing buildings, it's like we can ignore whether the building is blue or green, and whether it houses a bunch of small companies or one big corporation. Instead, we look at things like what material is it made from, how many floors it has, and so on. In arguments, these features are things like the nature of the premises and conclusion, and whether the argument is valid or not. These are things most people pick up naturally, but the discomfort comes from not feeling like there's a "starting point" to analyzing what you see. But that too is something that you can use to your advantage
Using your November 2018 example, I'll briefly touch on how you can crush that question pretty quickly. First, I'm looking for something—anything—notable in the stimulus. Some wording, some structure, whatever jumps out at me, which I can then use to kill off answers. Maybe it's a flaw, maybe it's something absolute, maybe it's a quirky idea. In this case, there's a conclusion at the end of the stimulus, and it features wording that "the proportion...cannot have increased substantially." That's somewhat interesting, and one would figure the conclusion in the correct answer would be somewhat similar (not exact, but at least would deal with "proportion" or some synonym). So, with that thought in mind, go right now and look at the conclusions in all five answers. Do NOT go on with this explanation until you look at each answer and compare conclusions. Eliminate any that don't match
somewhat.
Answers (A), (D), and (E) each deal with averages increasing, which doesn't seem all that similar (and it's not, since that's what the stimulus talks about in its base
premise—they are trying to reverse things here and trip you up). Great, I'll sideline those for the moment and look more closely at (B) and (C), which have conclusions that are both about proportions. Stop again and examine just (B) and (C)—which is better to you?
(B)'s conclusion is about a proportion not increasing, so identical to the stimulus, and (C)'s is about a proportion increasing. If I was forced right now to choose an answer, it would be (B) based on the language similarity. But, I don't really want to operate that way, and LSAC likes to invert language (think things like: "some attending" = "some are not absent"), so I'm going to look more closely at each.
So, I turn to the premise in the stimulus that is underneath that conclusion at the end. In this case, it's about a small average increase in weight in the prior eight years. So, I want a premise that's about averages (and if it's about a small increase, that would be excellent). Answer choice (B) fits the bill perfectly, and looks really good. Answer choice (C) uses a premise about "a substantial number," and that's not what I want. So, it's out. That leaves me with (B), and as it turns out, that's the right answer.
Note: I never had to deeply dive into the exact meaning of the relationships in each answer. I could knock out certain answers based on things that don't match up. And then I could wait until the end to make sure the specifics of my answer (or whatever contenders I have) were correct.
In a way, there's a Sesame Street aspect to these questions, where you are looking to knock out the things that aren't like the other ones. In this case the stimulus is my model, and I compare any and all points I need to in order to knock out wrong answers.
Please let me know if that helps. Thanks!