When a Certain X Ray Is Compton Scattered at Right $\lambda$

Multiple Choice

When a certain X ray is Compton scattered at right angles to its initial direction,the shift in its wavelength is $\lambda$ _c = 2.4 pm (1 picometer = 10^-12 m) .If the wavelength of this X ray is 15.4 pm,the wavelength of the scattered X ray must be closest to

A) 2.4 pm
B) 0.15 pm
C) 18 pm
D) 13 pm
E) 170 pm