Matrix `M_(r)` is defined as ,`M_(r)=[(r,r-1),(r-1,r)],r in N ;` value of `det(M_(1))+det(M_(2))+det(M_(3))+..............+det(M_(2007)) is ` `(A) 2007 (B) 2008 (C) (2008)^(2) (D) (2007)^(2) `