Two Side-By-Side Coherent Light Sources Radiate at 600 Nm

Multiple Choice

Two side-by-side coherent light sources radiate at 600 nm.The phase difference between these two sources at a point in space is 0.582 radians.The path difference between the two sources could be

A) 43.5 nm
B) 55.6 nm
C) 62.4 nm
D) 75.9 nm
E) 87.4 nm