We should not choose A because incorrectly ordered. And even if we worded it correctly, we would get a double negative, Do you not never...
We would only consider B correct if the will
stood before the I
, in which we case we would have "Never will I understand her." Negatives at the beginning of a sentence add emphasis. In this case, we have to invert the subject and verb.
As for C, check out the reason why you should not use it here
For Christ's sake, why did you not search the forum for an answer or an existing thread before starting a new thread?