[单选题]
X-rays of wavelength 0.2 ok 0s*ikmnir n8x,*9b0u0yab 0 nm are scattered by a metal. The wavel8jxxvjlp:8xl.k+ 1 q+oo-a jlength shift is observed tlx8l +8lkp-jjx. v:xoa + 1ojqo be $2.1 \times 10^{-12} \; m$ at a certain scattering angle measured relative to the incoming X-ray. What is the scattering angle?
A. $20^{\circ}$
B. $40^{\circ}$
C. $60^{\circ}$
D. $80^{\circ}$
Post time 2024-1-22 00:41:22