Fill four letters (left to right) to complete the pattern: M _ _ O M M N _ _ M _ _ N O M M N _ _ M

Introduction / Context:
The visible scaffolding shows repeated substrings around M, N, O with a fixed order. We need to restore four letters so the whole string respects that macro-order everywhere.

Given Data / Assumptions:
Four blanks appear at multiple positions; the chosen 4-letter sequence is placed left to right.

Concept / Approach:
A repeating fragment “M O N M” matches the visible clusters (…M O M M N… and …N O M M N…). Testing this insert across all gaps preserves the consistent ordering.

Step-by-Step Solution:

Verification / Alternative check:
Check each junction; the macro-pattern remains intact.

Why Other Options Are Wrong:
They force local inversions (e.g., N before required O) or duplicate adjacency mismatches.

Common Pitfalls:
Assuming alphabetical order rather than the document’s internal motif.

Final Answer:
M O N M