A Light Bulb Burns in Front of the Center of a 40-Cm

Multiple Choice

A light bulb burns in front of the center of a 40-cm wide mirror that is hung vertically on a wall.A man walks in front of the mirror along a line that is parallel to the mirror and twice as far from it as the bulb.The greatest distance he can walk and see the image of the bulb at all times is:

A) 20 cm
B) 40 cm
C) 60 cm
D) 80 cm
E) 120 cm