1. Until a specific consent to adoption or a relinquishment is executed by a parent of the child and an approved home study investigation pursuant to NRS 127C.840 is obtained, no person may:
(a) Petition any court for the appointment of a guardian; or
(b) Be appointed the temporary guardian,
Ê of the person of the child to be adopted.
2. A parent may sign a specific consent to adoption or relinquishment if the parent is in the custody of a law enforcement agency or the child is in the custody of an agency which provides child welfare services.