Which of the following is the square of an odd number?

Options

A. 256
B. 361
C. 144
D. 400

Answer

To determine which of the following numbers is the square of an odd number, we will evaluate each option provided: 256, 361, 144, and 400.

### Step-by-step Solution:

1. **Identify the options**: We have four numbers to evaluate: 256, 361, 144, and 400.

2. **Calculate the square roots of each option**:
- For **256**:
\[ \sqrt{256} = 16 \quad (\text{since } 16 \times 16 = 256) \]
- For **361**:
\[ \sqrt{361} = 19 \quad (\text{since } 19 \times 19 = 361) \]
- For **144**:
\[ \sqrt{144} = 12 \quad (\text{since } 12 \times 12 = 144) \]
- For **400**:
\[ \sqrt{400} = 20 \quad (\text{since } 20 \times 20 = 400) \]

3. **Determine if the square roots are odd or even**:
- **16** (from 256) is even.
- **19** (from 361) is odd.
- **12** (from 144) is even.
- **20** (from 400) is even.

4. **Identify the odd number**: From the square roots calculated, the only odd number is **19**, which corresponds to **361**.

5. **Conclusion**: Therefore, the number that is the square of an odd number is **361**.

### Final Answer:
The square of an odd number is **361**.