"Child Placing Agency" means a governmental organization or an agency organized pursuant to the nonprofit corporation act, Act No. 162 of the Public Acts of 1982, being sections 450.2101 to 450.3192 of the Michigan Compiled Laws, for the purpose of receiving children for their placement in private family homes for foster care or for adoption. The function of a child placing agency may include the investigation of applicants for adoption and the investigation and certification of foster family homes and foster family group homes as provided in this act. The function of a child placing agency may also include the supervision of children who are 16 or 17 years of age and who are living in unlicensed residences as provided in section 5(4).