Select the option in which the pair of letter-clusters share the same relationship as that shared by the given letter-clusters.

AM : EQ

AM ==> (A+4) (M+4) ==> EQ

Option (a) RS : VX

RS ==> (R+4) (S+4) ==> VW

The above-given logic is not applicable here. So this is not the correct answer.

Option (b) LB : JF

LB ==> (L+4) (B+4) ==> PF 

The above-given logic is not applicable here. So this is not the correct answer.

Option (c) GH : KE

GH ==> (G+4) (H+4) ==> KL

The above-given logic is not applicable here. So this is not the correct answer.

Option (d) PT : TX

PT ==> (P+4) (T+4) ==> TX

Hence 'TX' will come in place of the question mark.