Select the option that is related to the fifth letter-cluster in the same way as the second letter-cluster is related to the first letter-cluster and the fourth letter-cluster is related to the third letter-cluster.
SERIOUS : FTJSVPT :: UNKNOWN : OVOLXPO :: WARNING : ?
1
BXOSOJH
2
XBSOJOH
3
BXSOJOH
4
BXSOOJH