Difficulty: Medium
Correct Answer: VTL
Explanation:
Introduction / Context:This question tests a substitution cipher where each letter is replaced by its opposite letter in the alphabet. This is commonly known as the Atbash pattern: A↔Z, B↔Y, C↔X, ..., M↔N. The example PROJECT → KILQVXG matches this opposite-letter substitution.
Given Data / Assumptions:
Concept / Approach:Identify that P→K, R→I, O→L, etc., corresponds to opposite-letter mapping. Then apply the same mapping to each letter of EGO in sequence to form the coded word.
Step-by-Step Solution: Using opposite-letter mapping: E ↔ V (E is 5th letter, V is 22nd) G ↔ T O ↔ L Now encode EGO: E → V G → T O → L So EGO → VTL.
Verification / Alternative check:Check consistency with the example: P becomes K, and O becomes L, which are known opposite pairs. Since the same mapping is used for all letters, EGO must become VTL without any shifting or reordering.
Why Other Options Are Wrong: SGD: corresponds to different mapping (like shifting) not opposite-letter substitution. VPU: would imply G→P which is incorrect in Atbash. MJN: does not follow opposite pairs for E, G, O. ETL: keeps E unchanged, breaking the substitution rule.
Common Pitfalls:Using + or - shifts instead of opposite mapping, reversing the word order, or mapping using A=0 style offsets can lead to wrong codes.
Final Answer:VTL
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