#7 - Local, Could Be True

[Dave Killoran]

Complete Question Explanation
(The complete setup for this game can be found here: lsat/viewtopic.php?t=11493)

The correct answer choice is (A)

Since 1 and 3 are both off, and since either 2 or 4 must also be off (cannot both be on), the maximum number of on switches here is four. Also, you cannot have only one switch on because it would have to be switch 1 (rule 3), and you cannot have three switches on because switch 3 would have to be one of them (rule 3). Further, if you try to have four switches on, those switches would have to be 4, 6, 7 and then either 2 or 5. But 4 cannot go with 2 or 5 (rule 2), so it is impossible to have four switches on, as well. That means there must be only two switches on:

• Two switches on: 2 and either 5, 6, or 7.

So the correct answer choice must come from one of those possible combinations. Answer choice (A) is correct as 2 and 7 can both be on.