(a) Child placing agencies, in placing children in private families, shall safeguard their welfare by a thorough investigation of each applicant and its home and its environment, carefully select the home in which the child is placed, and personally and adequately supervise each home and child until the child is legally adopted or released.
(b) All children placed in private families shall be, as far as it is practicable, placed with those of the same religious faith as the children themselves, or their parents.