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. SSTO
B. OOTU
C. TTOU
D. USTO

Explanation

To solve the question, we need to analyze the four groups of letters given and identify the one that is different from the others based on a specific pattern.

### Step-by-Step Solution:

1. **Identify the Groups**: The four groups of letters are:
- Option A: S-S-T-O
- Option B: O-O-T-U
- Option C: T-T-O-U
- Option D: U-S-T-O

2. **Analyze Each Group**:
- **Option A (S-S-T-O)**: The letter 'S' appears twice.
- **Option B (O-O-T-U)**: The letter 'O' appears twice.
- **Option C (T-T-O-U)**: The letter 'T' appears twice.
- **Option D (U-S-T-O)**: No letter is repeated; each letter appears only once.

3. **Identify the Pattern**: In Options A, B, and C, there is a repetition of one letter, while in Option D, all letters are unique.

4. **Conclusion**: Since Options A, B, and C have one letter that is repeated, and Option D does not have any repeated letters, we can conclude that Option D is the different one.

### Final Answer:
The group that is different is **Option D: U-S-T-O**.

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