The final question of a game sometimes asks you to substitute a rule. Many people find these questions very difficult, but they don’t have to be. You should ask yourself what the main effect of the rule is.
If J is in, K is in. That forces N out.
If N is in, K is out. That forces J out.
So J and N can never go together, because of the combination of the first and second rules. And if J is in, and N is out, then K must be in, because we always need one of either N or K (the first rule).
So the right answer has to force N out if J is in, and force J out if N is in. Any secondary effect of a rule is almost the only way the LSAT can make a rule substitution answer work.
Answer choice D is CORRECT. It captures all of this information. If J being in causes N to be out, then K to has to be in, thanks to the first rule. Everyone works out the same.
A gets the second rule backwards, and so it has a different effect.
B has a different effect as well. Previously, it was possible to have K, O and L all in together. Now this can’t happen. And this answer also ignores the main effect of the second rule: now J no longer forces K in.
C is way off base. There was no such relation between O and K in the original setup, and this new rule leave J with no effect on K.
E contradicts the old setup. The original rules combine to the effect that if N is in, O and L are in. See the setup for more detail on this point.
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