A person walks at a velocity v in a straight line forming an angle a with the plane of a plane mirror. Determine the velocity \[{{v}_{rel}}\] at which he approaches his image, assuming that the object and its image are symmetric relative to the plane of the mirror.

• A. \[2v\,\text{sin}\,\alpha \]
• B. \[2v\cos \alpha \]
• C. \[v\sin \alpha \]
• D. \[v\cos \alpha \]