Hi! I'm taking the LSAT tomorrow and would love a bit of last minute help on this one to boost my confidence.

https://classic.7sage.com/lsat_explanations/lsat-34-section-4-game-4/

In the explanation, JY explains that answer B is correct using a thought process I cannot seem to grasp despite the number of times I watch the video. if J is in, then P is in - no problem. but then to say that when J is in, O and N can also be in confuses me...I understand that looking left of J - taking the contrapositive - O and N are in. but in doing so, don't you have to leave J out since it requires the contrapositive of J to get O and N in? I must be missing something super basic here. please help :) Thanks!

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