Find the odd one in the following group:

$\begin{array}{llll} Q,W,Z,B & B,H,K,M & W,C,G,J & M,S,V,X \end{array}$

1. $Q,W,Z,B$
2. $B,H,K,M$
3. $W,C,G,J$
4. $M,S,V,X$