Two coherent sources of light $S_1 $ and $S_2$ are placed in a line as shown. Two screens are placed perpendicular to $S_1S_2$ at A and B . It is observed that at point P a bright fringe is seen , then at point Q.

Question

(a)dark fringe occurs

(b)bright fringe occurs

(c)no fringe is seen

(d)screen B will be completely bright