In Nucleophilic Acyl Substitution Reactions Under Basic Conditions,____________

In nucleophilic acyl substitution reactions under basic conditions,____________.

A) protonation of the carbonyl group is followed by nucleophilic attack
B) loss of the leaving group is followed by formation of an acylium ion
C) an SN2 reaction occurs
D) the nucleophile must be a weaker base than the leaving group
E) nucleophilic addition to the carbonyl is followed by loss of a leaving group