Food includes everything edible, so you must select "Yes" at the kiosk, even if it is just candy. This will send you to Agriculture, where they will ask you about the type of food you bring and they may X-ray your baggage. I have done this many times at different airports, usually on the way from Europe to Canada. Very often, if you mention that you are going straight to Canada (food only in checked baggage) and the bags are checked through, they don't care any further and let you go.

Plenty of foods are allowed nowadays, the main exceptions are fresh fruits, meat and some dairy items (hard cheese is OK).