In a psychiatric paper I have encountered a sentence which is unclear to me:
It would clearly be preferable if all clinicians and researchers used the same terminology and DSM categories are but one option.
I'm interested in the meaning of the last turn of speech, i.e.
but one option. I think this is some sort of idiom, but I can't figure out its sense, it may be "the best option" as well as "the last option" or "the worst option". Also, it will be interesting to learn how to use this phrase properly.