"0.92%" wasn't an answer
0.92 and 0.0092 were answers with no accompanying units. What would you have put?
Percent is not a unit, percent is a definitive description of a numerical relationship.
I would have selected the value which corresponds to the one part in every hundred relationship which meets the definition of percent.
And that could have been the least correct answer, as the test maker is allowed to define the terms for the test.
And then I would have challenged the answer key.
And I may or may not have been vindicated, in either case I would not lose any sleep over it.