SSC Steno Grade C and D 7 Aug 2025 Shift 2 Paper

Four of the following five pairs follow a similar letter-coding pattern. Identify the one that does not belong to the group.
CRUSH: XIFHS
BLAST: YOZHG
FROWN: UILDM
HAPPY: SMNMB
SNAIL: HMZRO
Question: Which of the following pairs is the odd one out?