Two Slits in an Opaque Barrier Each Have a Width

Multiple Choice

Two slits in an opaque barrier each have a width of 0.020 mm and are separated by 0.050 mm.When coherent monochromatic light passes through the slits the number of interference maxima within the central diffraction maximum:

A) is 1
B) is 2
C) is 4
D) is 5
E) cannot be determined unless the wavelength is given