Which is the next shape in this picture :
Source: Iranian Ph.D. University entrance exam 2017
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Consider the following augmentation to the set of shapes
The rule for going from shape $N$ to $N+1$ is
Reflect all segments in the blue-red axis which are within $N$ segments of the red side. Then rotate the blue-red axis anti-clockwise.
Hence, the next shape will be
The fourth one