Light with a Wavelength of 644 Nm Uniformly Illuminates a Single

Multiple Choice

Light with a wavelength of 644 nm uniformly illuminates a single slit. What is the width of the slit if the first-order dark fringe is located at $\theta$ = 0.125°?

A) 9.42 × 10^-4 m
B) 7.60 × 10^-4 m
C) 4.71 × 10^-4 m
D) 3.80 × 10^-4 m
E) 2.95 × 10^-4 m