The Diagram Shows a Single Slit with the Direction to a Point

Multiple Choice

The diagram shows a single slit with the direction to a point P on a distant screen shown. At P, the pattern has its maximum nearest the central maximum. If X and Y are the edges of the slit, what is the path length difference (PX) - (PY) ?

A) $\lambda$ /2
B) $\lambda$
C) 3 $\lambda$ /2
D) 2 $\lambda$
E) 5 $\lambda$ /2