Explanation:

- Arrange digits of 7148356 in ascending order: 1345678

- Now, check each digit's position in original number and sorted number:

- 7: Original 1st, sorted 7th (changed)

- 1: Original 2nd, sorted 1st (changed)

- 4: Original 3rd, sorted 3rd (unchanged)

- 8: Original 4th, sorted 7th (changed)

- 3: Original 5th, sorted 2nd (changed)

- 5: Original 6th, sorted 4th (changed)

- 6: Original 7th, sorted 5th (changed)

- Only one digit (4 at position 3) remains in the same place after sorting.

- Option 1: None — Incorrect; at least one unchanged.

- Option 2: One — Correct.

- Option 3: Two — Incorrect; only one unchanged.

- Option 4: Three — Incorrect; only one unchanged.

Option 2 is correct.