The correct option is D 1m
Plane Mirrors always produce a virtual and erect image having the same size as that of the object irrespective of the position of object.
Height of the object, ho=1 m
We know,
Height of the object is equal to height of the image for a plane mirror.
⇒hi=ho=1 m
∴ Height of the image, hi=1 m
Hence, the correct answer is OPTION D.