"wants" are unnecessary
- this would be bad for the producers and sellers, as it would make us buy less! not the correct choice.
the firm has the best price
-yes, but this is irrelevant if we're not interested in the product in the first place...
a particular product is a "need"
-yes! this is the main goal, and the correct answer!
the product is the same as other firm's products
-then why buy it? it would be counter-productive!