I believe the answer is: C.By comparing a message written in both hieroglyphics and Greek, scholars were able to translate the hieroglyphic symbols.
Since the 6th century, the ancient greek and egyptian civilizations has already involved with one another through trades and travelling scholars. Because of this, cultural assimilation happened between the two, and many writings in greek actually depict a simialr writing that could be found in egyptian hieroglyphics.
