But that's not how they ask. It's usually something like "would you have a problem convicting the defendant of the crime they are accused of if you were convinced beyond all reasonable doubt that they had, in fact, committed said crime?" They don't say "Do you know what jury nullification is?"
I agree on the general indirection they use. However my answer to the specific question you posed is "no, I'd have no problem". But if it were eg a drug charge, then I wouldn't consider the relevant criminal law to be constitutional (life, liberty, and the pursuit of happiness, for starters), and thus the defendant is innocent because there is no crime to have been committed. My judgment wouldn't be to save one sympathetic person from being convicted of what is otherwise a legitimate crime, but rather over the validity of the law itself.
In general they will ask you a bunch of questions to trip up anyone who might be too clever, but they can't ask about jury nullification directly (lest they give anyone else ideas). If you answer in the expected common sense way, and don't boast about your reasoning, it's going to be very hard for them to claim perjury.
And if they use "will", it's perfectly normal to wonder why one would ask such a strange question. It would totally read as "we're gonna find a case to test you on that teehee".
