In the book crossover what important information does josh learn about his father that he didn't know before

From his studies of coptic, champollion knew that the egyptian word for "sun" was pronounced rah. he wrote down the first two letters of that sound, ra. next he put a question mark for the unknown middle hieroglyph. then, at the end, he wrote ss, the sound of the last two hieroglyphs. he studied the combination: ra ? ss. suddenly he remembered a famous pharaoh whose name appeared in ancient greek chronicles and also in the biblical book of exodus: rameses, or ramesses. could this be a hieroglyphic representation of ramesses' name? based on the excerpt, what detail did champollion need to conclude that the hieroglyphics might represent ramesses’s name?

Plz change it i can not change this sentences .

Which statement best completes its flow of reasoning