The correct option is A 3
Since the fan has three blades, the central angle is divided into 3 equal parts. This gives 360∘3=120∘.
Angle of rotation is the smallest angle for which the figure can be rotated to coincide with itself.
So, the degree of rotation of the fan is 120∘.
∴ Order of rotational symmetry =360∘minimum angle of rotation=360∘120∘=3