Atbash mapping (mirror alphabet) on each letter ACFJ : ZXUQ :: EGIN : ?

Introduction / Context:
Here the relation uses the Atbash (mirror) cipher: each letter maps to its symmetric counterpart in the alphabet (A↔Z, B↔Y, C↔X, etc.).

Given Data / Assumptions:

• ACFJ maps to ZXUQ.
• We apply the same mirror mapping to EGIN.
• Alphabet symmetry pairs sum to 27 if A=1 … Z=26.

Concept / Approach:
For any letter L with numeric value n, its mirror is 27−n. Do this for each letter independently to transform the word.

Step-by-Step Solution:

Verification / Alternative check:
Applying the mirror mapping again to VTRM returns EGIN, showing the mapping is its own inverse.

Why Other Options Are Wrong:

• VUSQ/UTRP/VRPM: Each has at least one letter that does not satisfy the 27-sum mirror rule for E, G, I, N.

Common Pitfalls:
Attempting constant forward/backward shifts; forgetting that Atbash maps A→Z, not A→W.

Final Answer:
VTRM