In YDSE apparatus shown in figure wavlength of light used is `lambda`. The screen is moved away form the source with a constant speed v. Initial distance between screen and plane of slits was D.
At a point P on the screen the order of fringe will
A. `(2D)/(v)`
B. `(D)/(v)`
C. `(3D)/(2v)`
D. `(3D)/(v)`