At the conclusion of a dispositional hearing on a petition for the commitment of the guardianship and custody of a child, the court shall enter an order of disposition:
(a) dismissing the petition in accord with section six hundred thirty-two; or(b) suspending judgment in accord with section six hundred thirty-three; or(c) committing the guardianship and custody of the child in accord with section six hundred thirty-four; provided, however, that an order of disposition committing the guardianship and custody of the child may not be entered after the child's eighteenth birthday, unless the child consents. An order of disposition shall be made, pursuant to this section, solely on the basis of the best interests of the child, and there shall be no presumption that such interests will be promoted by any particular disposition.
N.Y. Family Court Law § 631