Concept:Each group consists of three consecutive letters written in reverse alphabetical order.
Explanation:Start from ZYX: Z, Y, X are the last three letters in reverse order (X, Y, Z reversed).
Next is WVU: W, V, U are the three letters before X,Y,Z, also reversed.
Then TSR: T, S, R are the next three letters reversed.
Following the pattern, the next set should be the three letters before R, S, T, which are O, P, Q, written in reverse order as QPO.
Answer:QPO (Option A)
