I think the first question I would ask to A would be “If I ask b if you are true what would they say?” If they give me an answer that means b is not random if they don’t give me an answer i know be is random.
If I know b is not random I would ask C this question , “If I ask a If you are true what would they say?” If they dont give you an answer a is random
If they give you an answer C is random
The last question,(if figured out that random is either a or c is random you can ask this question to C)
“If I ask the truth among you and da is yes what would they say?”
If they say da c is true
If they say ja c is false
(Ask they same if figured out that B is random in first question)