67. A plan may acquire and hold bonds or other securities issued by a corporation, a cooperative association or a cooperative agricultural association:(a) if they are fully secured by real estate or by shares, preferred shares or bonds or other securities allowable for investment by the plan under this Division;
(b) if they are fully secured by equipment of the corporation of the cooperative association or of the cooperative agricultural association, and if one or the other, as the case may be, has paid in full the interest on its other debts during the 10 years preceding the acquisition of the bonds or other securities by the plan;
(c) if the common or preferred shares of the corporation or of the cooperative agricultural association or the shares or preferred shares of the cooperative association are allowable for investment by the plan under section 68 or the first paragraph of section 69;
(d) if they are fully secured by a corporation or a cooperative agricultural association whose common or preferred shares are allowable for investment by the plan under section 68 or the first paragraph of section 69;
(e) if they are fully secured by a cooperative agricultural association whose shares or preferred shares are allowable for investment by the plan under section 68 or the first paragraph of section 69.