In each of these question, four groups of letters are given. Three of them are alike in a certain way while one is different select the one which is different.

Options

A. DEB
B. HIF
C. NOL
D. RTP

Explanation

To solve the question, we need to analyze each group of letters and identify the pattern in the operations performed on the letters. Let's break it down step by step.

### Step-by-Step Solution:

1. **Identify the Groups**: We have four groups of letters:
- Group A: D, E, B
- Group B: H, I, F
- Group C: N, O, N
- Group D: R, T, P

2. **Analyze Group A (D, E, B)**:
- From D to E: D (4) + 1 = E (5)
- From E to B: E (5) - 3 = B (2)
- **Operation Pattern**: +1, -3

3. **Analyze Group B (H, I, F)**:
- From H to I: H (8) + 1 = I (9)
- From I to F: I (9) - 3 = F (6)
- **Operation Pattern**: +1, -3

4. **Analyze Group C (N, O, N)**:
- From N to O: N (14) + 1 = O (15)
- From O to N: O (15) - 1 = N (14)
- **Operation Pattern**: +1, -1

5. **Analyze Group D (R, T, P)**:
- From R to T: R (18) + 2 = T (20)
- From T to P: T (20) - 4 = P (16)
- **Operation Pattern**: +2, -4

6. **Compare the Patterns**:
- Groups A and B both follow the pattern of +1, -3.
- Group C follows a different pattern of +1, -1.
- Group D follows the pattern of +2, -4.

7. **Conclusion**: The group that is different from the others is Group C (N, O, N) because it does not follow the same operation pattern of +1, -3 as Groups A and B, and it also does not follow the +2, -4 pattern of Group D.

### Final Answer:
The group that is different is **Group C: N, O, N**.

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