Correct option is C
In Code 1 according to given table JUNCTION is changed into QFMXGRLM

Similarly CUSTOMER is written into XFHGLNVI by code 1.
In code 2 we add alphabetic number by 2,4,6,8,10,12,14,16. by this code CUSTOMER is not changed into XFHGLNVI.
In code 3 we add alphabetic number by 1,2,3,4,5,6,7,8.by this code CUSTOMER is not changed into XFHGLNVI.
In code 4 we add alphabetic number by 2 . by this code CUSTOMER is not changed into XFHGLNVI.