Image Formation by Plane Mirror Reflection

Steps:

• Draw incident rays from object O to points of reflection on the mirror.
• Apply law of reflection: angle of incidence equals angle of reflection at each point.
• Extend reflected rays backward behind the mirror.
• Image forms at intersection of backward extensions, equidistant from mirror as O.

Why B is correct:

• B marks the point where backward extensions intersect, forming virtual image per plane mirror law (object and image symmetric about mirror).

Why the others are wrong:

• A: Lies on mirror surface, ignoring virtual image behind mirror.
• C: Position in front of mirror, contradicting virtual nature of reflection.
• D: Incorrect intersection, violating equal angles of reflection.

Final answer: B