You are makming that Officer do some legal research on the subject. "Over 10 years ago" is vague. Depending on exactly when it happened is critical to the outcome. Read the article linked at the bottom and think carefully about these issues.
1. Did you get that job? If not then you did not benefit from it.
2. How did you adjust status? Did you need to use 245(i) and pay the penalty fee? That could help.
3. There is no waiver for false claim to USC made on or afgter 9/30/1996. Read INA 212(a)(6)(C) How old were you and what were your parents' status?
You would have to be deportable for having been inadmissible at time of admission in addition to being deportable just because of this. INA 237(a)(3)(D) is False claim to USC.
HOWEVER, prior to a very recent change to the Form I-9, the box you checked was marked USC or a national. A recent court ruling said that the alien could assert that he "thought he was a "national" simply because he was living in the U.S." The Form I-9 was changed after that, now the two designations have seperate boxes.
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thanks for your time...no i didnt get the job. i adjusted based on marriage to a usc.