e0a709…: “Right of a sad trapezoid”

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Below we have plotted a discrete “sampling” of a vector field:

Let $C$ be a circle of radius $3$ centered at the origin drawn in a counterclockwise fashion. What conclusions seem to be true?

This is a gradient field. This is not a gradient field. This field has positive curl. This field has negative curl. $\oint _C \vec {F}\dotp \d \vec {p} < 0$ $\oint _C \vec {F}\dotp \d \vec {p} = 0$ $\oint _C \vec {F}\dotp \d \vec {p} > 0$

Note that the radius of the circle is irreverent.