Explanation:

- Replace vowels (O, I, U, E) with the previous letters in the alphabet:

- O becomes N

- I becomes H

- U becomes T

- E becomes D

- Replace consonants (B, L, Q) with the next letters in the alphabet:

- B becomes C

- L becomes M

- Q becomes R

- The transformed word is: CNMHRTD

- Analyze the frequency of letters in the transformed word:

- Each letter in "CNMHRTD" is unique.

- Correct Option: Option: 1, None