Find the Missing Code in the 5-Letter Pattern: BYCXW, CXDWV, EVFUT, GTHSR, ? — determine the next 5-letter block.

Introduction / Context:
Letter-series questions often operate column-wise (position by position). Each position can advance forward or backward with regular steps, producing a structured 5-column evolution.

Given Data / Assumptions:

• Blocks: BYCXW, CXDWV, EVFUT, GTHSR, ?
• Work column-wise across the five positions.

Concept / Approach:
Extract each column and look for arithmetic progressions on alphabet indices (A=1 … Z=26), noting some move forward (+) while others move backward (−).

Step-by-Step Solution:
Col1: B(2) → C(3) → E(5) → G(7): +1, +2, +2 → next +2 → I(9)Col2: Y(25) → X(24) → V(22) → T(20): −1, −2, −2 → next −2 → R(18)Col3: C(3) → D(4) → F(6) → H(8): +1, +2, +2 → next +2 → J(10)Col4: X(24) → W(23) → U(21) → S(19): −1, −2, −2 → next −2 → Q(17)Col5: W(23) → V(22) → T(20) → R(18): −1, −2, −2 → next −2 → P(16)Thus the next block is I R J Q P.

Verification / Alternative check:
The 1/2/2 stepping pattern repeats across symmetric forward/backward columns, reinforcing IRJQP as the only consistent continuation.

Why Other Options Are Wrong:

• KPOLN, KPLON, JOKPO: they do not satisfy all five column progressions simultaneously.

Common Pitfalls:
Reading left-to-right as a single word transformation; the safe method is column-wise progression tracking.

Final Answer:
IRJQP