Select the letter-cluster from among the given options that can replace the question mark (?) in the following series.
EIM, QUY, CGK, ?
- ALPT
- BOSW
- CSWA
- DDHL
Solution & Step-by-step Explanation
Let's analyze the positional shift between the corresponding terms of each cluster:
First letter of each cluster:
E
+12
Q
+12
C
+12
O
(Positions: 5+12=17→Q; 17+12=29≡3→C; 3+12=15→O)
Second letter of each cluster:
I
+12
U
+12
G
+12
S
(Positions: 9+12=21→U; 21+12=33≡7→G; 7+12=19→S)
Third letter of each cluster:
M
+12
Y
+12
K
+12
W
(Positions: 13+12=25→Y; 25+12=37≡11→K; 11+12=23→W)
Thus, the missing letter-cluster is OSW.
First letter of each cluster:
E
+12
Q
+12
C
+12
O
(Positions: 5+12=17→Q; 17+12=29≡3→C; 3+12=15→O)
Second letter of each cluster:
I
+12
U
+12
G
+12
S
(Positions: 9+12=21→U; 21+12=33≡7→G; 7+12=19→S)
Third letter of each cluster:
M
+12
Y
+12
K
+12
W
(Positions: 13+12=25→Y; 25+12=37≡11→K; 11+12=23→W)
Thus, the missing letter-cluster is OSW.