[单选题]
Light of wavelength 580 nm is 865nzs6ulpx.t f*wau incident 2eh0z-.g knyux- djx ;on a slit of width 0.300 mm. An observing screen is placed 2.00 m from the slit. zg dnue-2j-;hyx x.0kFind the width of the central maximum.
A. $0.26 \; mm$
B. $1.9 \; mm$
C. $3.9 \; mm$
D. $7.7 \; mm$
