(a) Except as otherwise provided in subsection (b) of this section, a trustee who invests and manages trust assets owes a duty to the beneficiaries of the trust to comply with the prudent investor rule set forth in this article.
(b) The prudent investor rule, a default rule, may be expanded, restricted, eliminated or otherwise altered by the provisions of a trust instrument. A trustee is not liable to a beneficiary to the extent that the trustee acted in reasonable reliance on the provisions of the trust instrument.