Final answer:
The decree on the Rosetta Stone represents a historical document written in multiple languages and was passed by a council of priests affirming the royal cult of Ptolemy V.
Step-by-step explanation:
The decree on the Rosetta Stone represents a historical document written in multiple languages. The stone contains a decree passed by a council of priests affirming the royal cult of Ptolemy V. It is inscribed in hieroglyphic Egyptian, demotic Egyptian, and Greek, and the Greek inscription on the stone was the key to deciphering the others.