Which of the followin options is correct?

Options

A. `{:("Haploid","Diploid"),("Secondary oocyte","Primary spermatocyte"):}`
B. `{:("Haploid","Diploid"),("Secondary spermatocyte","Secondary oocyte"):}`
C. `{:("Haploid","Diploid"),("Primary oocyte","Secondary spermatocyte"):}`
D. `{:("Haploid","Diploid"),("Ovum","Spermatid"):}`

Explanation

To solve the question regarding which option is correct, we will analyze each statement provided in the options step by step.

### Step-by-Step Solution:

1. **Understanding the Definitions**:
- **Primary Oocyte**: It is the initial stage of oocyte development and is diploid (2n).
- **Secondary Oocyte**: It is formed from the primary oocyte after the first meiotic division and is haploid (n).
- **Primary Spermatocyte**: It is formed from spermatogonium and is diploid (2n).
- **Secondary Spermatocyte**: It is formed from the primary spermatocyte after the first meiotic division and is haploid (n).
- **Spermatid**: It is produced from the secondary spermatocyte after the second meiotic division and is also haploid (n).
- **Ovum**: It is the mature female gamete and is haploid (n).

2. **Analyzing Option 1**:
- **Statement**: Secondary oocyte is haploid whereas primary spermatocyte is diploid.
- **Evaluation**: This statement is correct. The secondary oocyte is indeed haploid, and the primary spermatocyte is diploid.

3. **Analyzing Option 2**:
- **Statement**: Secondary spermatocyte is haploid, and secondary oocyte is diploid.
- **Evaluation**: This statement is incorrect. While the secondary spermatocyte is haploid, the secondary oocyte is also haploid, not diploid.

4. **Analyzing Option 3**:
- **Statement**: Primary oocyte is haploid, and secondary spermatocyte is haploid.
- **Evaluation**: This statement is incorrect. The primary oocyte is diploid, while the secondary spermatocyte is indeed haploid.

5. **Analyzing Option 4**:
- **Statement**: Ovum is haploid whereas spermatid is diploid.
- **Evaluation**: This statement is incorrect. The ovum is haploid, but the spermatid is also haploid, not diploid.

6. **Conclusion**:
- After evaluating all options, we find that only **Option 1** is correct.

### Final Answer:
The correct option is **Option 1**: Secondary oocyte is haploid whereas primary spermatocyte is diploid.