The number of images formed by two plane mirrors inclined at an angle ${45}^{\circ }$ of an object placed symmetrically between mirrors is

The correct option is C 7
To find the number of images we have to find $$\frac{360}{\theta }$$ where $\theta$ is the angle between the plane mirrors.
Here $\theta ={45}^o$ $$⟹\frac{360}{45}=8$$
Since 8 is even, we have to subtract one from it to get the total number of images
Therefore number of images is $8-1=7$