BOOKS - if 2 then K is fourth, if 1 then C is fourth - from ROCKY - 2 we know the O is correct but not the R from ROUGE - 1 (the O), and not the Y from DELAY - 0 so one of C or K must be correct. If BOOKS is 2 then not the B or S from BONDS - 1 (the O) andd not the second O from QUOTH - 0 so K would be fouth but if BOOKS - 1 (the first O) then the K is wrong and C must be the third.