A. The membership of an association shall consist of:
1. Every holder of an account or one or more shares of guaranty capital issued by the association.
2. Every borrower from the association, as long as his loan remains unpaid and he remains liable to the association for the payment thereof, and every obligor of an investment made by the association. Each of such members shall be known as a borrowing member.
B. Each joint ownership and each joint obligation shall constitute one membership.