(a) A trustee shall diversify the investments of the trust unless the trustee reasonably determines that, because of special circumstances, the purposes of the trust are better served without diversifying.
(b) In the absence of an express provision to the contrary in the terms of the trust, a trustee without liability, may continue to hold property received into the trust at its inception or subsequently added to it or acquired pursuant to proper authority if and so long as the trustee, in the exercise of good faith and of reasonable prudence, considers the retention to be in the best interest of the trust or in furtherance of the purposes of the trust. The property shall include any successor-in-interest to the original property. The property may also include, among other things, stock in the trustee if a corporation and stock in any corporation controlling, controlled by, or under common control with the trustee.