Explanation:

- Section 26 of the Specific Relief Act deals with the rectification of instruments.

- Rectification can be done when there is a mistake in drafting the document (called an instrument).

- The relevant mistake should be a mistake in framing the instrument, which could be due to fraud or accident.

- This does not directly cover "mutual mistake" or "bilateral mistake" in the sense of mistakes in agreements, but specifically mistakes in the document itself.

Correct Answer:

Option:2, Mistake in framing of the instrument