B. The prudent investor rule, a default rule, may be expanded, restricted, eliminated, or otherwise altered by the provisions of a trust. A general authorization in a controlling document authorizing a trustee to invest in such assets as the trustee, in his sole discretion, may deem best, or other language purporting to expand the trustee’s investment powers, shall not be construed to waive the rule of subsection A unless the controlling document expressly manifests an intention that it be waived (i) by reference to the “prudent man” or “prudent investor” rule, (ii) by reference to power of the trustee to make “speculative” investments, (iii) by an express authorization to acquire or retain a specific asset or type of asset such as a closely held business, or (iv) by other language synonymous with clause (i), (ii) or (iii). A trustee shall not be liable to a beneficiary for the trustee’s good faith reliance on a waiver of the rule of subsection A.