Final answer:
The distance between Manjula and her image after moving 1 meter closer to the mirror is 8 meters, as both the actual and apparent distances in front of and behind the mirror are considered. Therefore, the correct option is D.
Step-by-step explanation:
Manjula is observing her image in a plane mirror. Initially, the distance between herself and the mirror is 5 meters. When she moves 1 meter towards the mirror, she is now 4 meters away from it. However, since a plane mirror creates an image that appears to be the same distance behind the mirror as the object is in front of it, the image will also move 1 meter closer. Therefore, the total distance between Manjula and her image is now 4 meters (in front of the mirror) + 4 meters (behind the mirror), which equals 8 meters.