Not all works of art represent something, but some do, and their doing so is relevant to our aesthetic experience of them; representation is therefore an aesthetically relevant property. Whether a work of art possesses this property is dependent upon context. Yet there are no clear criteria for determining whether context-dependent properties are present in an object, so there cannot be any clear criteria for determining whether an object qualifies as art.
The reasoning above is questionable because it fails to exclude the possibility that
A. because some works of art are nonrepresentational, there is no way of judging our aesthetic experience of them
B. an object may have some aesthetic properties and not be a work of art
C. aesthetically relevant properties other than representation can determine whether an object is a work of art
D. some works of art may have properties that are not relevant to our aesthetic experience of them
E. some objects that represent things other than themselves are not works of art