Answer:
The missing part pf speech can be adjective.
It would be example
Hope this helps
Have a great day/night
The answer to the question "Which of the following sentences most clearly expresses an opinion?" is B.
This practice is divisive, it is unfair, it is archaic.
The word unfair is a key word to knowing that is in opinion, because there is no factual evidence to tell you that it is fair or unfair. Opinions can be backed by facts, but can not be proven.