The Pupil of a Cat's Eye Narrows to a Slit

Multiple Choice

The pupil of a cat's eye narrows to a slit of width 0.7 mm in daylight.Assuming a wavelength of 500 nm,what is the angular resolution? (1 nm = 10^-9 m)

A) 0.7 x 10^-3 rad
B) 6 x 10^-3 rad
C) 0.7 x 10^-4 rad
D) 6 x 10^-4 rad