Which of the follwing numbers is not a perfect square ?

Options

A. 1444
B. 3136
C. 961
D. 2222

Answer

To determine which of the following numbers is not a perfect square, we will analyze each option and check their unit digits.

### Step-by-Step Solution:

1. **List the Options**:
- Option 1: 1, 4, 4
- Option 2: 3, 1, 3, 6
- Option 3: 9, 6, 1
- Option 4: 2, 2, 2, 2

2. **Understand Perfect Squares**:
- A perfect square is a number that can be expressed as the square of an integer. The unit digits of perfect squares can only be 0, 1, 4, 5, 6, or 9.

3. **Check Unit Digits**:
- **Option 1**: The unit digits are 1 and 4. Both are perfect square unit digits.
- **Option 2**: The unit digits are 3 and 6. The digit 6 can be a unit digit of a perfect square (like 6² = 36), but 3 cannot.
- **Option 3**: The unit digits are 9 and 1. Both are perfect square unit digits.
- **Option 4**: The unit digits are all 2. The digit 2 cannot be a unit digit of any perfect square.

4. **Conclusion**:
- Since option 4 contains the digit 2, which cannot be a unit digit of any perfect square, we conclude that **option 4 (2, 2, 2, 2) is not a perfect square**.

### Final Answer:
**Option 4: 2, 2, 2, 2 is not a perfect square.**

---