Based on the English alphabetical order, three of the following four letter-cluster pairs are alike in a certain way and thus form a group. Which is the letter-cluster pair that DOES NOT belong to that group?
(Note: The odd one out is not based on the number of consonants/vowels or their position in the letter-cluster.)

Logic: 1st + 1 = 3rd, 2nd -5 = 4th

Option A: TY → UT

T +1 = U

Y -5 = T

Option B: SX → TS

S +1 = T

X -5 = S

Option C: KI → LP

K +1 = L

I - 5 =D ≠ P (does not follow)

Option D: YD → ZY

Y +1 = Z

D - 5 = Y

Thus, the correct option is (c).