Ans: B
A is the image rotating the given plane figure anticlockwise about the point $O$ through $180^\circ$.
A is the image rotating the given plane figure anticlockwise about the point $O$ through $180^\circ$.
B is the image rotating the given plane figure anticlockwise about the point $O$ through $270^\circ$.
We cannot get the image in option C by rotating the given plane figure.
D is the image rotating the given plane figure anticlockwise about the point $O$ through $90^\circ$.
Therefore, B is the correct answer.
