In which of the following instances would the independence of the auditor most likely not be considered to be impaired?

Select one:

a. They have been retained as the auditor of a large manufacturing company that has loaned the auditor $6000.

b. They have been retained as the auditor of a charitable entity in which the spouse of the auditor serves as treasurer.

c. They have been retained as the auditor of a company from which the auditor purchased his or her latest motor vehicle at normal list price.

d. They have been retained as the auditor of a company in which the auditor's investment club owns a 10% interest.