Why Is One Equivalent of AlCl₃ Required for the Transformation

Why is one equivalent of AlCl₃ required for the transformation shown here?

A) Either the oxygen or the chlorine in the acyl chloride can attach to the Al atom in AlCl₃.
B) AlCl₃ is needed to produce the acyl chloride during the course of the reaction.
C) The product forms a complex with the AlCl₃.
D) The product would rearrange unless there were extra. AlCl₃ present.
E) Both benzene and the acyl chloride form complexes with the AlCl₃.