Three of the given options are alike in a certain way. However, one option is not like the other three.

Select the option which is different from the others.

The postional value of alphabets is shown in given chart:-

The logic used in this question is:-

Logic - Alphabets is in continue manner.

Option 1:- S T U : U V W ✅

Here, alphabets is in continue manner.

Option 2:- R  T  S : H  S  T ❌

Here, alphabets is not in continue manner.

Option 3:- D  E  F : F  G  H ✅

Here, alphabets is in continue manner.

Option 4:- F G  H : H  I  J ✅

Here, alphabets is in continue manner.

Hence, the answer is RTS : HST.