Two Side-By-Side Coherent Light Sources Radiate at 633 Nm

Multiple Choice

Two side-by-side coherent light sources radiate at 633 nm.At a point in space where the path difference to these two sources is 30 nm,the phase difference could be

A) 0.238 radians
B) 0.298 radians
C) 0.324 radians
D) 0.356 radians
E) 0.429 radians