Plane Mirror Image Formation Steps:

• Light from the girl reflects off the mirror to the boy's eyes.
• The image forms virtually behind the mirror, equidistant from it as the girl is in front.
• Since the boy and girl are side by side at equal distances from the mirror, their images appear side by side behind the mirror.
• The boy perceives the girl's image as if she were standing symmetrically behind the mirror relative to his position.

Why A is correct:

• A shows the virtual image behind the mirror, at the same perpendicular distance and lateral position as the girl, per the law of reflection in plane mirrors.

Why the others are wrong:

• B places the image in front of the mirror, violating virtual image formation.
• C positions it above or below, ignoring equal distances and side-by-side alignment.
• D locates it behind the boy, contradicting symmetric positioning relative to the mirror.

Final answer: A