Select the incorrect statement with respect to enzymes used in DNA replication:

Options

A. Topoisomerase can unwind the DNA helix.
B. Helicase joins the Okazaki fragments.
C. DNA Ligase holds the fork open and stabilizes.
D. All of the above.

Explanation

To solve the question regarding the incorrect statement about enzymes used in DNA replication, we will analyze each statement provided in the options.

### Step-by-Step Solution:

1. **Understand the Role of Topoisomerase**:
- Topoisomerase is an enzyme that helps to relieve the tension in the DNA helix during replication. It does this by making cuts in the DNA strand, allowing it to unwind and prevent supercoiling.
- **Statement**: "Topoisomerase can unmind the DNA helix."
- **Evaluation**: This statement is correct because topoisomerase does help in unwinding the DNA.

2. **Understand the Role of Helicase**:
- Helicase is the enzyme responsible for unwinding the DNA double helix by breaking the hydrogen bonds between the nitrogenous bases.
- **Statement**: "Helicase is the fragments of the Okazaki."
- **Evaluation**: This statement is incorrect. Helicase does not fragment Okazaki fragments; instead, it unwinds the DNA strands. Okazaki fragments are formed on the lagging strand during replication.

3. **Understand the Role of DNA Ligase**:
- DNA ligase is an enzyme that joins Okazaki fragments on the lagging strand by sealing nicks in the sugar-phosphate backbone of DNA.
- **Statement**: "DNA ligase holds the fork open and stabilizes."
- **Evaluation**: This statement is incorrect. DNA ligase does not hold the replication fork open; rather, it seals the nicks between Okazaki fragments.

4. **Conclusion**:
- After evaluating the statements, we find that the statements regarding helicase and DNA ligase are incorrect. Therefore, the option that states "All of the above are incorrect" is also incorrect because the statement about topoisomerase is correct.
- Hence, the answer to the question is that the incorrect statement is related to helicase and DNA ligase.

### Final Answer:
The incorrect statement with respect to enzymes used in DNA replication is:
- "All of the above are incorrect." (Option D)