I think if "A" said "Hairless dogs did not exist in other locations prior to existing in Peru and Mexico" it would count as a NA, but because it says 'never' it's not necessary, because even if it were true (which it is) that hairless dogs had been found in places other than Peru and Mexico many centuries later, that wouldn't negate the conclusion.

Let's go dude I got the same score in November let's get this 170+ in January!!! I can't believe you've taken every PT that's insane. If anyone deserves this 170+ it's you. My technique is to literally never take full PT's. I select the question type I get wrong the most (for example in LR for me that's weaken, flaw, NA) then make 6-10 question sets of the "medium," "harder," and "hardest" questions from the first 58 PT's. Then once I feel good about all the questions I usually get wrong I'll take a practice test from 59 and beyond of only that section (LR or LG). I basically don't study RC because it's the hardest to improve on and if I can just get -1 or -0 on LG and LR I can afford up to -8 on RC. Also I feel like LR teaches a lot of the close reading skills necessary to improve on RC. I don't like full practice tests because I get burned out easily. Good luck!