9 images are noticed for an object placed infront of two plane mirrors inclined at an angle$\theta$ . Then the value of $\theta$ is     

Here it is not given in the question that object is placed symmetrically or asymmetrically.

(i) If it is placed symmetrically then

$n=\frac{2{\pi }^c}{\theta }-1\left(\text{irrespect}\text{of}\frac{{\text{2π}}^c}{\text{θ}}\text{even}\text{or}\text{odd}\right)$

Then $9=\frac{2\pi }{\theta }-1\Rightarrow \theta =36°$

(ii) If it is placed asymmetrically then

$n=\frac{2{\pi }^c}{\theta }\left(\text{given}\text{n}\text{is}\text{odd}\right)$

$9=\frac{2{\pi }^c}{\theta }\Rightarrow \theta =40°$

So from the given options possible answer is 36°.