I take it you meant "beer" not "best," and I would agree.
I hate to isolate one variable because I think they are all parts of whole, and the notion that there is one magic bullet is usually the kiss of death in terms of my attempts to maintain a lower weight over the long haul.
That said, if I had to pick the single biggest factor for me, it would definitely be booze in general and beer in particular. I'm sure I've recited it here before, but I'll never forget the moment during the second or third visit with my nutritionist when she was reviewing my food diary entries on MyFitnessPal: "What kind of beer is 300 calories?!?" She was referring to a can of Sip of Sunshine and that was a revelation for me. When you are trying to stay between 1,800 and 2,000 calories a day, giving away 300 at a time on beer is a big spend--too big for me. By comparison, most of the ciders or wines I drink are around 110-180 calories per serving; better still, Scotch and Irish whiskeys are around 65-70 calories per serving.