What Is the Limiting Angle of Resolution,in Degrees,for a Microscope $\times$

Multiple Choice

What is the limiting angle of resolution,in degrees,for a microscope with an objective 0.50 cm in diameter when viewing is done at 590 nm?

A) 2.1 $\times$ 10^-3
B) 4.1 $\times$ 10^-3
C) 7.2 $\times$ 10^-5
D) 8.2 $\times$ 10^-3
E) 1.4 $\times$ 10^-4