Yes, that is the only good answer. She obviously hasn’t done much big media, and there were other things besides the Truther issue that showed how nervous she was. One tip-off is that she wasn’t listening to Beck, and consequently was talking over him. Apparently, she doesn’t understand that unlike TV radio has no visual clues so you must listen.
As someone who has done a fair amount of radio and television, I can tell you that this is not uncommon. She wasn’t prepared for the question, wasn’t prepared for the medium, and failed to give a good answer. The press release that came out almost immediately after the interview I am sure reflects her actual view - she is not a Truther, but she bungled the interview and the damage was done.
I think the question was fair. Moreover, even if it hadn’t been asked, she was not doing well with Beck and it would have been a poor interview anyway (though not as bad as it was). I haven’t seen anyone comment on that, but if you go back and listen I think you’ll agree that the non-Truther part left a lot to be desired.