Each latter from the given question having some pattern.
- $JMP = J \overset{+3}\longrightarrow M\overset{+3}\longrightarrow P$
- $RUX = R\overset{+3}\longrightarrow U\overset{+3}\longrightarrow X$
- $UYB = U\overset{+4}\longrightarrow Y\overset{+3}\longrightarrow B$
- $EHK = E\overset{+3}\longrightarrow H\overset{+3}\longrightarrow K$
So, option $(C)$ does not belong to the group.