Consider a Single-Slit Diffraction Pattern Caused by a Slit of Width

Multiple Choice

Consider a single-slit diffraction pattern caused by a slit of width a. There is a maximum if sin $\theta$ is equal to:

A) slightly more than 3 $\lambda$ /2a
B) slightly less than 3 $\lambda$ /2a
C) exactly 3 $\lambda$ /2a
D) exactly $\lambda$ /2a
E) very nearly $\lambda$ /2a