Section 775. Order on hearing

(a) After hearing a petition under section
  seven hundred seventy-three, the court may:
    (i) dismiss the petition;
    (ii) grant the petition, making  such  placement,  if  the  court  was
  authorized to make such placement upon the original adjudication; or
    (iii)  terminate the prior order of placement and either discharge the
  respondent or place him on probation.
    (b) If the  court  grants  the  petition  and  orders  placement,  the
  respondent  shall thereupon be transferred to the custody of the person,
  agency or institution provided by the court's order.