Which of the following employees derives their income from a fee for the items sold?
a.
commission
b.
piece rate
c.
salaried
d.
tip

Answer is a. commission

commission : a payment to someone who sells goods that is directly related to the amount sold, or a system that uses such payments
piece rate : a way of paying for work that is based on a fixed rate for a particular amount done rather than the time it takes to do the job
salaried : a fixed amount of money agreed every year as pay for an employee, usually paid directly into his or her bank account every month
tip : a small amount of money given to someone who has provided you with a service, in addition to the official payment and for their personal use