Select the letter cluster that can replace the question mark (?) in the following series.
CSW, DUZ, EWC, FYF, ?, HCL
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → GAI
Each position of the cluster is checked on its own; after Z the count continues from A.
First letters C, D, E, F: 1 place ahead each time, so the missing letter is G, and then H, which matches the last term
Second letters S (19), U (21), W (23), Y (25): 2 places ahead each time; 2 ahead of Y are Z, A, and 2 ahead of A gives C, which matches the last term
Third letters W (23), Z (26), C, F: 3 places ahead each time (3 ahead of Z are A, B, C); so 3 ahead of F (6) is \(6+3=9\), I, and \(9+3=12\) gives L, which matches the last term
So the missing cluster is GAI.