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. BD
B. SU
C. PN
D. WY

Explanation

To solve the question, we need to analyze the given groups of letters and identify the pattern among them. The groups provided are:

1. B D
2. S U
3. P
4. W Y

### Step-by-Step Solution:

**Step 1: Analyze the first group (B D)**
- The letters B and D are two positions apart in the alphabet.
- B is the 2nd letter and D is the 4th letter.
- Therefore, moving from B to D involves adding 2 (B + 2 = D).

**Step 2: Analyze the second group (S U)**
- The letters S and U are also two positions apart in the alphabet.
- S is the 19th letter and U is the 21st letter.
- Therefore, moving from S to U also involves adding 2 (S + 2 = U).

**Step 3: Analyze the third group (P)**
- The letter P stands alone and does not have a pair.
- P is the 16th letter. There is no addition or subtraction involved here.

**Step 4: Analyze the fourth group (W Y)**
- The letters W and Y are two positions apart in the alphabet.
- W is the 23rd letter and Y is the 25th letter.
- Therefore, moving from W to Y involves adding 2 (W + 2 = Y).

**Step 5: Compare the groups**
- Groups 1 (B D), 2 (S U), and 4 (W Y) all involve adding 2 to get from the first letter to the second letter.
- Group 3 (P) does not follow this pattern since it stands alone and does not involve any addition.

### Conclusion:
The group that is different is **P**, as it does not follow the same pattern of adding 2 like the other groups.

### Final Answer:
**Option 3: P is the different one.**

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