If a mirror is placed on the line MN, then which of the answer figures is the right image of the given figure ?

A vertical mirror is placed, so the object on the left will appear right in reverse position and vice-versa.

So the rhombus at the top left will be reversed and will now appear at top right, thus the last two options will be eliminated.

Also, in the question figure, the triangle (pointing left) at bottom left will change its position and direction, and will now be pointing right at bottom right position, hence second option is the right image.

=> Ans - (B)