Well, I did it again, and my frustration is really mounting.
I went with "des ordannances" thinking that 1) "some" is implied here (one goes to the pharmacy for some/any prescriptions) and 2) prescriptions are countable.
Since the answer is "les", I have to ask: does the use of "on" (instead of "nous") automatically imply the statement is general and thus the use of le/la/l'/les?
Would these then be correct? Nous servons du café. -and- On serve le café. That does not seem right to me.
Or, is it just because I translated just the part of the sentence ("or for prescriptions at the pharmacy") and not that part of the sentence as part of the whole sentence...?
Maybe I need clarification on how to distinguish "general" statements from "some/any" statements or learn if there is some additional concept that I need to consider when deciding between les and des.