AFAIK, (and IANAL), you would have to be certain the questions did not incriminate you. In other words, "pc86, were you or were you not on your couch May the 5th at 8PM EST?" "I plead the fifth." "Your honor, this doesn't incriminate the witness." "pc86, you must answer the question because it is non-incriminating." And of course if it was incriminating, the appellate lawyers would win resoundingly.

Logically, it would follow that if you don't know what a question IS, you can 'plead the fifth' to it on the basis that it could be incriminating. But again, IANAL.