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.

MARS : NLBZSQTR :: PLUTO : QOMKVTUSPN :: EARTH : ?

FDBZSQUSIG

Pattern followed is :

MARS : NLBZSQTR

M lies b/w N & L , A lies b/w B & Z , R lies b/w S & Q , S lies b/w T & R

PLUTO : QOMKVTUSPN

P lies b/w Q & O , L lies b/w M & K , U lies b/w V & T , T lies b/w U & S , O lies b/w P & N 

Similarly ,

EARTH : ?

E lies b/w F & D , A lies b/w B & Z , R lies b/w S & Q , T lies b/w U & S , H lies b/w I & G .

FDBZSQUSIG , is correct answer .