Select the related group of letters from the given alternatives: WUS is to DFH as MKI is to which group?

Introduction / Context:
This analogy uses a symmetric alphabetic transformation known as a letter complement or Atbash type mapping. WUS is mapped to DFH, and you must discover which option shows the correct mapping for MKI. The core idea is that each letter is replaced by another letter such that their positions add up to a fixed constant, commonly 27, so that A pairs with Z, B with Y, and so on.

Given Data / Assumptions:

• The base coding is WUS mapped to DFH.
• The second original group is MKI, whose code is unknown.
• The options are LJH, GEC, OQS, and NPR.
• Alphabet positions are A = 1, B = 2, ..., Z = 26.
• We suspect that each letter is transformed into its complement with respect to 27, meaning position of original letter + position of coded letter = 27.

Concept / Approach:
We test the complement idea on WUS and DFH. If for each letter pair the sum of their alphabet positions is 27, the mapping is confirmed as a symmetric complement. We then apply this same mapping to MKI and see which option matches the result. This method, often called Atbash type coding, is common in reasoning questions that involve mirrored alphabet positions.

Step-by-Step Solution:
Step 1: Find positions of W, U, and S. W is 23, U is 21, and S is 19. Step 2: Find positions of D, F, and H. D is 4, F is 6, and H is 8. Step 3: Check the sums: 23 + 4 = 27, 21 + 6 = 27, and 19 + 8 = 27. Step 4: This confirms that each coded letter is the complement of the original letter with respect to 27. Step 5: Apply the same rule to MKI. M is 13, K is 11, and I is 9. Step 6: Compute the complements: for M(13), 27 - 13 = 14, which is N; for K(11), 27 - 11 = 16, which is P; for I(9), 27 - 9 = 18, which is R. Step 7: Combine these letters to form NPR and compare with the options. NPR appears as option d.

Verification / Alternative check:
To double check, we can apply the mapping in reverse from NPR back to MKI. N is 14, P is 16, and R is 18. Subtract each from 27: 27 - 14 = 13 (M), 27 - 16 = 11 (K), and 27 - 18 = 9 (I), which reproduces MKI exactly. No other option, when each letter is complemented with respect to 27, will give MKI, so NPR is the only group that satisfies the symmetric complement rule used in WUS : DFH.

Why Other Options Are Wrong:
LJH, GEC, and OQS do not have letter positions that sum to 27 with the letters of MKI. For instance, if we tried M with L, the sum is 13 + 12 = 25, not 27. Similarly, pairing K with J gives 11 + 10 = 21. These failed sums demonstrate that they do not follow the same complement pattern. Therefore, these options cannot be the correct coded forms under this analogy.

Common Pitfalls:
A common mistake is to look for a constant forward or backward shift, such as adding or subtracting the same number of positions, without noticing the symmetric nature of the mapping. Another pitfall is to miscalculate letter positions, especially near the middle of the alphabet. Recognising that A pairs with Z, B with Y, C with X, and so on helps quickly identify complement relationships like W with D or M with N.

Final Answer:
Using the same 27 complement mapping that converts WUS to DFH, the group MKI is converted to NPR.