Putting it all together

[Juliyamai]

In chapter 4 on 3D Numbered ordering in the section Putting it All Together, the game with the detectives PT 53, S2, G3 question #13. I do not understand the explanation of why does Y has to confess. From question it adds another condition saying that Z Confessed (so Z is C), then 4th is N, 5th and 6th is C and 7th is N. I know that T could go both ways, but why is Y has to be C. I set up frames, but still not getting it about Y. Thank you

[patrice.antoine]

It comes down to what it says in the prompt "if Z is the SECOND suspect to confess".

That means that there is a first suspect to confess, and the only suspect that can come before Z in this scenario is "Y". So we know here that Y MUST be the first to confess. Answer choice (E) violates this inference.

[Juliyamai]

Oh thank you. I guess it was a play on words also, so now I got it