Light of wavelength \[\lambda \]strikes a photo-sensitive surface and electrons are ejected with kinetic energy E. If the kinetic energy is to be increased to 2E, the wavelength must be changed to \[\lambda '\] where [MP PET 1997]

• A.            \[\lambda '=\frac{\lambda }{2}\]                                    
• B.            \[\lambda '=2\lambda \]
• C.            \[\frac{\lambda }{2}<\lambda '<\lambda \]               
• D.            \[\lambda '>\lambda \]