Fill the gaps to complete the reverse–then-forward alphabet pattern: ZYX_W_YZZ_XWWXY_. Choose the 4-letter string that correctly fills all blanks in order.

Introduction / Context:
Letter-series completion tasks measure a candidate’s ability to detect simultaneous local and global patterns in alphabetic runs. This item has a visible “descending then ascending” motif, with four blanks to be filled by one ordered 4-letter string chosen from the options.

Given Data / Assumptions:

• Visible skeleton: Z Y X _ W _ Y Z Z _ X W W X Y _
• English alphabet order; wrap-around is not required.
• One option (a 4-letter sequence) must fill the 4 blanks in order.

Concept / Approach:
The string begins with a strict reverse run Z, Y, X, then appears to pivot toward a forward movement (…W, X, Y, Z…). Many classic constructions mirror around a central turn. Hypothesis: the missing letters are precisely the forward block W, X, Y, Z to transition cleanly from the reverse segment into an organized forward cluster that repeats locally.

Step-by-Step Solution:
1) Insert W at blank1 to complete the reverse tail: Z, Y, X, W.2) Insert X at blank2 to begin a forward push: …W, X, Y, Z…3) Insert Y at blank3 to continue the forward quartet near Z Z: …Y, Z, Z, X…4) Insert Z at blank4 so the tail reads …W, W, X, Y, Z with smooth local symmetry.Resulting string: Z Y X W W X Y Z Z X W W X Y Z.

Verification / Alternative check:
Read through the finished line: the early Z→Y→X descent passes into an overlapping forward cluster W→X→Y→Z that reappears as interlocking sub-blocks (…W X Y Z… and …X W W X Y Z…), which is typical of exam patterns that splice a clean forward run into a reverse-to-forward hinge.

Why Other Options Are Wrong:

• WYXZ / WXZY / XYZW: Each scrambles the pure forward W→X→Y→Z order. Those permutations introduce local inversions (e.g., Y before X) that break the intended hinge from reverse to forward.

Common Pitfalls:
Many solvers focus on only the immediate neighbors of each blank and miss the overarching “reverse then forward” dual structure. Always test a candidate fill across all blanks and scan the entire line for clean runs.

Final Answer:
WXYZ