Electrons with de-Broglie waveelngth `lambda` fall on the target in an X-ray tube.The cut- off wavelength of the emmitted X-rays is:

Options

A. `lambda_0 = (2 h)/(m c)`
B. `lambda_0 = lambda`
C. `lambda_0 = (2 m c lambda^2)/h`
D. `lambda_0 =(2 m^2 c^2 lambda^3 )/(h^2)`