In each of the following questions, four numbers are given. Out of these three are alike in some way but rest one is different. Choose the one which is different from the other.

Options

A. 399
B. 325
C. 197
D. 145

Answer

To solve the problem of identifying the odd number out of the given options (399, 325, 197, 144), we will analyze each number to see if they relate to perfect squares.

### Step-by-Step Solution:

1. **Identify the Numbers**: The numbers given are:
- Option 1: 399
- Option 2: 325
- Option 3: 197
- Option 4: 144

2. **Check Each Number**:
- **Option 1: 399**
- Subtract 1: \(399 - 1 = 398\)
- Check if 398 is a perfect square: It is not.

- **Option 2: 325**
- Subtract 1: \(325 - 1 = 324\)
- Check if 324 is a perfect square: \(18^2 = 324\) (This is a perfect square).

- **Option 3: 197**
- Subtract 1: \(197 - 1 = 196\)
- Check if 196 is a perfect square: \(14^2 = 196\) (This is a perfect square).

- **Option 4: 144**
- Subtract 1: \(144 - 1 = 143\)
- Check if 143 is a perfect square: It is not.

3. **Group the Numbers**:
- From the checks, we find that:
- Option 2 (325) and Option 3 (197) both lead to perfect squares when we subtract 1.
- Option 4 (144) also leads to a perfect square when considered as \(12^2\) itself.
- Option 1 (399) does not lead to a perfect square.

4. **Identify the Odd One Out**:
- Since Options 2, 3, and 4 are associated with perfect squares, while Option 1 (399) is not, we conclude that:
- **The odd number out is Option 1: 399.**

### Final Answer:
The number that is different from the others is **399**.