Which detail from the excerpt explains the purpose of the three languages on the Rosetta Stone

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Read the excerpt from The Riddle of the Rosetta Stone.

But what did the passages in Egyptian mean? Did they contain exactly the same message as the Greek passage? The last sentence of the Greek text said, "This decree shall be inscribed on a stela [slab] of hard stone in sacred [hieroglyphic] and native [demotic] and Greek characters," so it seemed clear that the inscription was the same in all three languages. That way, the priests' statement could be read by Egyptians who understood Greek, as well as by those who knew only one or both of the Egyptian languages. But the scholars were still far from being able to decipher either the hieroglyphs or the demotic writing.

Which detail from the excerpt explains the purpose of the three languages on the Rosetta Stone?

A. The last sentence of the Greek text said, "This decree shall be inscribed on a stela [slab] of hard stone in sacred [hieroglyphic] and native [demotic] and Greek characters."

B. [S]o it seemed clear that the inscription was the same in all three languages.

C. That way, the priests' statement could be read by Egyptians who understood Greek, as well as by those who knew only one or both of the Egyptian languages.

D. But the scholars were still far from being able to decipher either the hieroglyphs or the demotic writings.

Answer:

The detail that explains the purpose of the three languages on the Rosetta Stone is:

C. That way, the priests' statement could be read by Egyptians who understood Greek, as well as by those who knew only one or both of the Egyptian languages.

Explanation:

The Rosetta Stone opened the door to deciphering hieroglyphs. It contained the same text written in three different languages, one of them being Greek, which finally allowed the hieroglyphs inscribed on the stone to be understood. But what was the purpose of having all three languages on the stone? As is stated in letter C, it allowed everyone - people who understood Greek, as well as people who knew one or both of the Egyptian languages - to understand the priests' statements inscribed. The purpose was, therefore, to reach all audiences possible and necessary.