What should come in place of ? in the given series based on the English alphabetical order?
CKS LRC ? DFW MMG

Given: 

CKS LRC ? DFW MMG

The pattern seems to be:
1st letter increases by +9
2nd letter increases by +7
3rd letter decreases by -16

Comparing "CKS" and "LRC"

C → L (+9)
K → R (+7)
S → C (-16)
Comparing "DFW" and "MMG"
D → M (+9)
F → M (+7)
W → G (-16)
Using the same pattern for the missing term:
Applying to "LRC"
L → U (+9)
R → Y (+7)
C → M (-16)
So, the missing term is UYM.

Therefore, the correct answer is (b). ​​