Can we rotate the figure some angle smaller than 360 degrees and have it match up with its original image? The answer to that is "no". Any such rotation will change the image to something else. Therefore, this figure does not have any point symmetry (aka rotational symmetry).
Can we reflect one half of the figure over some line to get the other half? The answer here is also "no". The diagram has no reflectional symmetry either.
Plane symmetry is ruled out because that only applies to 3D settings.
