An Advantage of a Straight-Commission Plan for Paying Salespeople Is

An advantage of a straight-commission plan for paying salespeople is that it:

A) Is a variable cost.
B) Enables sales managers to increase their control over the sales force.
C) Is a good plan when maximum incentive is needed for all the salespeople.
D) All of these are advantages.
E) Only two of the A-B-C are advantages.