[argc]

Maybe she got nervous and her brain stopped working for a minute? Has happened to me when asked to explain something I've designed or code I've written at work and for some unknown reason I got flustered and once that happens it can take some time before I can remember things that I normally know very well. Could explain making a mistake that makes absolutely no sense, I could totally see myself doing it. (I also think some people don't have this issue as much and might not understand how it can happen).