I'd have to say d. the hand, because every human (for the most part, no offence intended to anyone) has a hand and is able to make good (or bad, rather) use of it. It's what a person always has access to at any given time or place, even if they don't have access to one of the other options.
There is no exact weight. This is not no question on a homework sheet. Be yourself hunny. Don't worry about your weight.
Genetics. Genetics has a significant contribution and may predispose individuals to eating disorders. ...
Biochemistry. Individuals with eating disorders may have abnormal levels of certain chemicals that regulate such processes as appetite, mood, sleep and stress. ...
Psychology. ...
Culture. ...
Environment.
eat please