A. The court may appoint a guardian for a minor if the court finds that the appointment is in the best interest of the minor and that one of the following applies:
1. After being fully informed of the nature of a guardianship appointment, each living parent of the minor consents to the appointment of a guardian.
2. The parental rights of the living parents of the minor have been terminated.
3. The minor is at least sixteen years of age and is not the subject of an open dependency case pursuant to title 8 and, based on a preponderance of the evidence, no parent of the minor is willing or able to exercise the powers and duties granted by the court to a guardian.
B. A guardian who is appointed by will as provided in section 14-5202 and whose appointment has not been prevented or nullified under section 14-5203 has priority over any guardian who may be appointed by the court but the court may proceed with an appointment on a finding that the testamentary guardian has failed to accept the testamentary appointment within thirty days after notice of the guardianship proceeding.