In which of the following circumstances would a covered member's independence be impaired with respect to a nonissuer client?

a$)$ the member is designated to serve as guardian of a friend's children if the need arises, and the friend's estate, which would be held in trust for the children, holds significant stock ownership in a client entity.

b$)$ the member's spouse qualifies because of geographical residence to belong to a client's credit union, and all transactions with the credit union are conducted under normal operating practices.

c$)$ the member belongs to a client golf club that requires members to acquire a share of the club's debt securities$.$

d$)$ the member owns municipal utlity bonds issued by a client, and the bonds are not material to the member's wealth.