For each of the following statements, identify the audit assertion that it relates to:

a. Sales are made to customers that do not have approved credit.

b. Goods not ordered by the customer are shipped.

c. Unit prices on customer invoices are incorrect.

d. Invoices are not posted to customer accounts.

e. Goods are shipped but not invoiced.

f. Sales may be made to unauthorized customers.

g. Fictitious sales may be recorded.