One Drawback to the Expense Control Plan Where the Salespeople

One drawback to the expense control plan where the salespeople pay their own expenses is that:

A) The sales reps do not like it.
B) It cannot be used when salespeople are in a training program.
C) It cannot be used when a sales rep is developing a new territory.
D) It discourages reps from performing nonselling activities.
E) None of these is an inherent drawback.