Mistake on February 1994 Logic Game?? Forum

[revahp00]

Hey everyone- Long time troll here first time poster

I'm currently studying for lsats and came across a logic game from February 1994 where I believe there is a mistake on the part of the "makers".

The question asks: If O is selected for the first Sunday, which one of the following is a concerto that must also be selected:
(A)
(B)
(C)
(D)
(E)

The correct listed answer is (B), and I can see how (B) can be correct. That is, if O is first then J cannot be selected because O, under the condition proposed in the question stem, is first. And, since 2 of H, J, and K, must be selected, and since J cannot be selected with O, then naturally K must occur.
However, I can also see how (D) can be correct. My reasoning for why (D) can be correct is as follows: If O is selected then M cannot be selected, and if M is not selected then N must be selected. Does anyone see how my reasoning may be flawed? Thanks!

EDITED BY MOD.

[revahp00]

Actually found the flaw in my own reasoning after typing the whole darn thing out! Thanks.
For those who are interested I made a mistaken reversal of the contrapositive of N---> not (M)

[20121109]

Please do not post full texts of official LSAT questions.